This class relates to processes or means not otherwise classified
comprising (1) shafts or deep borings in the earth, commonly known
as wells, for the extraction of fluids from the earth, (2) shafts
or deep borings in the earth for inserting a fluid into the interstices
of a porous earth formation, usually to enable withdrawal of fluid from
a producing output well, (3) apparatus peculiarly adapted for treating
a well or for use in or with a well, or (4) processes of using,
making, or treating a well.

This class takes combinations of elements or process steps
relating to wells and going beyond the scope of subcombinations,
such as measuring or testing means or pumps, classifiable, per se,
in other classes. The class also takes subcombinations, such as
packers or expanding anchors, peculiar to wells. However, the class
does not take various intermediate combinations, such as devices
performing only a measuring or testing function or a pumping function,
which may include subcombinations, such as packers or expanding
anchors, as minor perfecting features.

Treating a well includes various miscellaneous processes or
apparatus relating to wells; typically, gravel layer forming, cementing,
washing or acidizing.

SECTION II - LINES WITH OTHER CLASSES AND WITHIN THIS CLASS

A. RELATIONSHIP TO CLASS 175, BORING OR PENETRATING THE EARTH

The relationship of Class 166 with boring or penetrating the
earth, classified in Class 175, is close both for historical and
functional reasons. The lines between Class 166 and Class 175 are
set forth in the class definition of the latter class with the exception
of the below noted reference to cementing. While Class 166 is generic
to processes including earth boring or penetrating steps no general
subclass has been provided in Class 166 for combinations with earth
boring since earth boring of some kind is always associated with
well making and the relationships expressed in the claims of patents
were thought to be better classified on other bases in this class,
see Class 175 subclasses 57+ and the search there noted
for earth boring processes, per se.

Generally in relation to apparatus Class 175 is more comprehensive
than Class 166 and takes combinations of Class 175 and Class 166
subject matter. Class 166 however, takes some miscellaneous subcombinations which
may be disclosed as used only in drilling operations but which are
in fact of general utility in wells, particularly when there is
no suitable subclass provided in Class 175 and a suitable subclass
is provided in Class 166.

Processes of cementing, plugging or consolidating as defined
in Class 166 subclass 21 are distinguished from drilling with fluid
processes classifiable in Class 175 subclasses 65+ by the
interruption of the actual earth cutting operation of the drilling
process. Thus a process which purports to be a drilling process
but which includes in its disclosure some indication that the actual earth
cutting has stopped to permit cementing, such as a statement that "drilling
is resumed" or that "after the cement has set",
will be considered a cementing process for Class 166. The fact
that a drilling tool stem or shaft is disclosed as the means for
delivering the cementing materials below ground or a disclosure
that drilling mud or drilling fluid is used as a carrier for or
a constituent of the cementing material will not preclude classification in
Class 166. Such processes in which drilling is interrupted to permit
cementing are classifiable in Class 166 even if the cementing step
is only normally or inferentially claimed. See, however (1) Note
in Class 166, subclass 21.

B. RELATIONSHIP TO PUMPS

The general line between Class 417, Pumps and Class 166 is
that if subject matter relating to a feature peculiar to a well
is claimed in combination with Class 417 subject matter, classification
is in Class 166. The following categories of subject matter more
specifically delineate this line.

a. Combinations of certain subcombinations, which if claimed,
per se, are classifiable in Class 166, those with Class 417 subject
matter are classifiable in Class 417. A recitation of a well broadly,
or with certain well features will not exclude a patent from Class
417. The following are examples of such features which would be
classifiable in Class 417:

i. a well tubing or conduit.

ii. structure in well tube to support a Class 417 device.

iii. a packer or anchor for sealing a Class 417 device in tube.

iv. a below ground check valve in pump inlet or outlet.

v. a valve which drains Class 417 device.

b. In examples iv. and v. it should be noted that a broadly
recited pump or pump barrel with an anchor, packer or drain valve
is classifiable in Class 166 in appropriate anchor, packer or valve
subclasses.

2. Class 417 Device Combined With Below Ground Separator
or Screen.

A well screen, as defined in Class 166, subclass 227, generally
contacts the earth wall of the well bore as a continuation of a
casing. A solids separator or inlet screen for a pump tube in a
well is generally disposed inside the casing and well screen. A
well type screen specifically described as such and claimed in combination
with a pump as more than an opening or a passage for fluid is classifiable
in Class 166. A gas separator or anchor disclosed as in a well,
even though claimed in combination with a Class 417 device is classifiable
in Class 166 (see Subclass References to Current Class, below),
except as noted in section D below. Further, a sediment trap or
deflector (e.g., sand trap) disclosed as in a well is also classified
in Class 166 (see Subclass References to Current Class, below) even
though claimed in combination with a pump.

3. Above Ground Well Structure Combined With Class 417 Device.

Generally the combination of a Class 417 device, whether above
or below ground, with above ground well apparatus for handling pumped
fluid or supporting a pump driving means is classifiable in Class
417. Note, however, that features which relate the well structure
to the earth, such as placing pipes below the frost line or embedded
foundation which also supports well casing will cause classification
in Class 166.

4. Below Ground Fluid Entrainment Type Pumps and Flowing
Wells.

a. Class 417 will take an aerating column, jet, gas lift
or other entrainment type pump, per se. See References to Other
Classes, below.

b. Class 166 will take Class 417 device as set forth in paragraph
(1) when the solely disclosed and claimed means for supplying all
the motive fluid to the device is located in the well and collects
the motive fluid by trapping or separating well fluid in the well
(e.g., gas anchor, packer with gas passage to central conduit etc.).

c. Class 417 will take subject matter similar to that in paragraph
(2) above when there is a specific description of means to supply
additional motive fluid from the earth surface or a point outside
the well. This classification prevails even though the additional
motive fluid may have been originally obtained from the same well.
Obviously combinations of these features with other well features
may cause classification in Class 166.

5. Summary of Well Feature.

a. The following features, claimed in combination with a
Class 417 device, are representative of the type of subject matter
in general which will cause classification in Class 166:

i. Any specific relationship of the Class 417 device or other
fluid conducting structure to the earth or earth formations as:
plural pumps in plural wells; single pump connected to a plurality
of wells; inlets from a plurality of earth formations; location
of parts in relation to the frost line in earth; lateral conduit
below ground; earth contacting well screen; and earth embedded support
for tubing or casing.

ii. Any specific relationship to well operation or structure,
such as: process steps in addition to installation, removal or operation
of a pump; control of pump or pumped fluid in response to a condition
sensed in a well; control or pump or pumped fluid in relation to operation
of another device in the well, other than mere flow check valves;
above ground separation of fluids leaving well for purposes other
than the production or removal of pump operating or motive fluid;
apparatus, not forming a part of the pump itself, for handling or manipulating
pump parts; passages for pumped fluid specifically described as
directing the fluid to wash, clean or otherwise treat the well;
sediment traps or deflectors; and gas separators (but see Section
4c above).

C. WELL SHAFTS AND METHODS AND THE LIKE ELSEWHERE CLASSIFIED

Well shafts or shafts sunk in the earth and structurally similar
to well shafts, and methods of operating wells are not all classified
in Class 166.

See References to Other Classes for classes that provide for
shaft structures and methods which are equivalent or very similar
to those found in Class 166.

D. DEVICES OR PROCESSES IN WELLS OR THE LIKE ELSEWHERE CLASSIFIED

Class 166 provides for various well treating and flow controlling
devices to be inserted into a well below the ground level, but other
classes also provide for similar devices. In cases of doubtful
classification the fact that a device is disclosed only for use
below ground in a well should incline classification towards Class
166.

Class 166 provides for example, for apparatus and methods
for fluid sampling in a well for cementing, washing, or mechanically
cleaning a well, acidizing or otherwise treating a formation, packing,
plugging, heating, cooling, dissolving paraffin, separating materials
in a well, (including liquids from liquids, gases from liquids and solids
from liquids), graveling or otherwise forming strainers in a well,
and anchoring devices in a well.

See References to Other Classes, below, for other classes
which take devices inserted in a well or analogous devices and processes
relating to such devices.

E. REFERENCES INTEGRAL TO AND EXTERNAL TO THIS CLASS

Subclass References to the Current Class, below, includes
both subclass references integral to Class 166 as well as references
to art areas external to this class.

Brushing, Scrubbing, and General Cleaning, for apparatus designed or adapted for cleaning for other
than well use
subclasses 104.05+ for pipe, tube, or conduit cleaner, subclass 249.1 for
a brush or broom flue cleaning implement or subclasses 249.2+ for
a scraper-type cleaning implement. (Lines With Other Classes and Within
This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Chemistry: Physical Processes,
subclass 232for processes of gas sampling involving the use of
sorbents or chemical treatments which may include a shaft sunk in
the ground to collect gas for analysis. (Lines With Other Classes
and Within This Class, Well Shafts and Methods and the Like Elsewhere
Classified.)

Chemistry: Physical Processes,
subclass 232for gas analyzing process for use in a gas well, involving
the use of sorbents. (Lines With Other Classes and Within This
Class, Devices or Processes in Wells or the Like Elsewhere Classified.)

Metal Working, appropriate subclasses for processes or apparatus
for assembling or disassembling well structures above ground, or
in which there is no special relationship with the well. See Subclass
References to the Current Class, above.

Geometrical Instruments, appropriate subclasses, for instruments, per se, for measuring distances,
angles, and the like in a well,
subclasses 302and 304+, for borehole direction or inclination
sensing and indicating. (Lines With Other Classes and Within This
Class, Devices or Processes in Wells or the Like Elsewhere Classified.)

Excavating,
subclass 182and subclasses 183+ for orange peel and
clamshell buckets, which may be inserted in a well. (Lines With
Other Classes and Within This Class, Devices or Processes in Wells
or the Like Elsewhere Classified.)

Fishing, Trapping, and Vermin Destroying,
subclasses 124+ for vermin destroying shafts sunk in the earth.
(Lines With Other Classes and Within This Class, Well Shafts and
Methods and the Like Elsewhere Classified.)

Static Structures (e.g., Buildings),
subclasses 19+ , 169.1+, 192+, 223.1, 245+,
and 261 for a masonry construction surrounding an open space which
may form a cistern or well wherein no feature peculiar to well operation, e.g.,
screens, pumps, driving points, shoes, etc., is defined. (Lines
With Other Classes and Within This Class, Well Shafts and Methods and
the Like Elsewhere Classified.)

Refrigeration,
subclasses 45+ for subject matter, including wells, for the use
and handling of liquefied gas. (Lines With Other Classes and Within
This Class, Well Shafts and Methods and the Like Elsewhere Classified.)

Measuring and Testing,
subclasses 151.01+ for subject matter relating to bore hole studies
and subclasses 863+ for soil gas sampling devices. (Lines
With Other Classes and Within This Class, Well Shafts and Methods
and the Like Elsewhere Classified.)

Measuring and Testing, appropriate subclasses, especially
subclasses 152.01+ for instruments, per se, (including subcombination means
such as packers or anchors for perfecting the measuring or Testing
Function) for bore hole studies and subclasses 863+ for
fluid samplers of general utility. Class 166 takes devices for
taking a sample of fluid from a potential producing horizon of a
well, but such sampling combined with measuring or testing or bore hole
study is in Class 73. Devices or methods for sampling gas from
the soil by means sunk into the ground to a point not far from the
surface of the ground are in Class 73, subclasses 863+.
(Lines With Other Classes and Within This Class, Devices or Processes
in Wells or the Like Elsewhere Classified.)

Expansible Chamber Devices,
subclasses 172+ for pistons, and particularly subclass 180, for an
elongated tubular well type plunger, and subclasses 240+ for
a piston having the side wall portion thereof provided with a peripheral axially
extending flexible lip. A piston which is fluid driven for treating
a well (e.g., for cementing) is classified in Class 166, subclasses
153+. (Lines With Other Classes and Within This Class,
Devices or Processes in Wells or the Like Elsewhere Classified.)

Gas Separation: Processes,
subclasses 241+ for degasification of liquid and other appropriate
subclasses for processes to be used near oil or gas wells to separate
gas from other constituents discharged from the well. Claims to these
processes may include a nominal recitation of the well process.
However, a detailed recitation of the well process or a recitation
of an input well receiving material from the separator indicates
classification in Class 166. See Subclass Refereneces to the Current
Class, above.

Gas Separation: Apparatus,
subclasses 155+ for degasifying means for liquid and other appropriate
subclasses for apparatus to be used near oil or gas wells to separate
gas from other constituents discharged from the well. Claims to
this apparatus may include a nominal recitation of the well. However,
a detailed recitation of the well or a recitation of an input well receiving
material from the separator indicates classification in Class 166.
See Subclass References to the Current Class, above.

Ammunition and Explosives,
subclasses 301+ for apparatus and methods for causing an explosion
in a well to break up a formation, clean a bore, or perform other
functions involving only an explosion. (Lines With Other Classes
and Within This Class, Devices or Processes in Wells or the Like
Elsewhere Classified.)

Planting,
subclasses 118+ for devices for placing fluids below the surface
of the earth without any expectation of recovering them and subclasses
89+ for dibbles. (Lines With Other Classes and Within
This Class, Well Shafts and Methods and the Like Elsewhere Classified.)

Fluid Handling,
subclasses 272+ for fire hydrants and subclasses 363+ for
ground supporting enclosures. (Lines With Other Classes and Within
This Class, Well Shafts and Methods and the Like Elsewhere Classified.)

Fluid Handling, appropriate subclasses for fluid handling devices of general
application and not having a specific location in a well or other
specific relationship to a well, especially
subclasses 67+ for such devices with destructible or deformable
element control other than valves or closures in wells destructible
by drilling, subclass 155 for gas lift valves for wells and subclass
515 for direct response valves in couplings for co-axial conduits.
(Lines With Other Classes and Within This Class, Devices or Processes
in Wells or the Like Elsewhere Classified.)

Pipes and Tubular Conduits,
subclasses 37+ for flow restrictors or pipes with flow restrictors;
and subclasses 100-178 for conduit structure of general utility,
including conduits disclosed only for use as well casings or tubings.
(Lines With Other Classes and Within This Class, Well Shafts and
Methods and the Like Elsewhere Classified.)

Pipes and Tubular Conduits,
subclasses 89+ for closures and plugs other than plugs which are
inserted into a prepositioned well conduit. (Lines With Other Classes
and Within This Class, Devices or Processes in Wells or the Like
Elsewhere Classified.)

Adhesive Bonding and Miscellaneous Chemical Manufacture, appropriate subclasses for process and apparatus for laminating
in general and see especially
subclasses 293+ and 423+ for inserting a core within a
tube combined with a laminating step. A process of lining a well
or conduit in a well is classified in Class 166. (Lines With Other
Classes and Within This Class, Devices or Processes in Wells or the
Like Elsewhere Classified.)

Heat Exchange,
subclass 45for a geographically installed heat exchanger that
may comprise a well. Heat exchange apparatus comprising part of
a well apparatus for producing or treating a well would be classified
in Class 166. (Lines With Other Classes and Within This Class,
Well Shafts and Methods and the Like Elsewhere Classified.)

Fire Extinguishers,
subclasses 2+ for processes for extinguishing or preventing well fires,
and also patents for apparatus for extinguishing or preventing fires
claiming no more of the well than cooperates with the fire extinguishing
or preventing means and also claiming some fire extinguishing or
prevention feature beyond a mere cap or casing head, means for diverting
flow or means for inserting a fluid into the well. See Subclass
References to the Current Class, above.

Boring or Penetrating the Earth,
subclass 1for processes or apparatus for boring including seismic
shock generation; subclasses 2+ for processes or apparatus
for boring by below ground explosion, and including a device for firing
a bullet or exploding a shaped charge from an inaccessible bore
to penetrate the formation, to enlarge the bore, or form a bore,
and including such device even when limited by disclosure to merely
perforating or cutting a casing or other wall member in the bore
if the device inherently causes penetration of the formation; subclasses
11+ for processes or apparatus for boring by directly applying
heat to fluidize or comminute the earth; especially subclass 12
for combustion of the earth formation itself and subclass 16 for
electrically produced heat; subclass 17 for processes or apparatus
including heating or cooling either within the bore or of the drilling
fluid (merely using drilling fluid to cool or heat is not included);
subclasses 40+ for processes or apparatus for boring including
signaling, indicating, testing or measuring and especially subclass
45 for tool direction or inclination measuring or indicating within
the bore; subclasses 57+ for earth boring processes, per
se, and especially subclass 59 for processes of taking samples of
solid earth formation including (1) retaining fluid in the solid
sample or (2) taking a separate fluid sample (processes of taking
a fluid sample only are in Class 166; see Subclass References to
the Current Class, above); subclass 77 for side wall tools fed laterally
of an existing bore hole (fluid conducting lateral probes sealed
to the well wall are in Class 166; see Subclass References to the
Current Class, above); subclasses 79+ for tool shafts which
are advanced relative to a guide (e.g., whipstock) insertable in
a well bore to change the direction of advance (means for guiding
an insertable element laterally of the well axis, e.g., whipstock,
per se, are in Class 166; see Subclass References to the Current Class,
above); subclass 84 for boring apparatus with an above ground cleaner
therefor; subclasses 98+ for a below ground tool drive motor
with an expansible anchor; subclasses 207+ for boring apparatus
with above ground means for handling drilling fluid or cuttings, especially
subclasses 209+ in which the means engages the bore entrance;
subclass 230 for boring apparatus including an expanding anchor;
subclasses 293+ for below ground hammer or impact devices
claimed, per se, (well devices combined with a jar for releasing a
stuck part are in Class 166; see Subclass References to the Current
Class, above); subclass 314 for boring apparatus combined with a
well type screen; and subclass 402 for an earth cutting casing shoe
type bit. (See Lines With Other Classes and Within This Class,
Relationship To Class 175, Boring or Penetrating The Earth, above.)

Boring or Penetrating the Earth, appropriate subclasses, for processes and apparatus
for boring or penetrating the earth, see particularly Lines With
Other Classes and Within This Class, above, and the search notes
located within this section. (Lines With Other Classes and Within
This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Liquid Purification or Separation,
subclasses 459+ for filters and strainers which may be used in
a well or as a pump intake. See Class 166, subclass 227 for the
line between Classes 166 and 210. (Lines With Other Classes and Within
This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Liquid Purification or Separation,
subclasses 294+ for diverse distinct separators, subclasses 322+ for
plural distinct separators, subclasses 348+ for a filter,
and subclasses 513+ for a gravitational separator. See
Subclass References to the Current Class, above.

Electric Heating,
subclasses 277+ for electric heaters, per se, for lowering into
a well. The combination of a heater and well structure is in Class
166. The well structure, for example, may be no more than a tubing
for flowing fluid from or into the well. (Lines With Other Classes
and Within This Class, Devices or Processes in Wells or the Like
Elsewhere Classified.)

Dispensing,
subclasses 356+ and the subclasses there noted for dipping type
dispensers not used in a well. (Lines With Other Classes and Within
This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Valves and Valve Actuation, appropriate subclasses for valves and valve actuators of
general application and not having a specific location in a well
or other specific relationship to a well, especially
subclass 76for impact actuated valves, subclasses 142+ for
a flow path with a single valve, and subclasses 341+ for
valves in which the valve actuator is the valve casing or a continuation
thereof. (Lines With Other Classes and Within This Class, Devices
or Processes in Wells or the Like Elsewhere Classified.)

Seal for a Joint or Juncture, for packing structure of general application particularly
subclasses 5+ for a packing between a casing and a relatively
movable sectional rod and subclass 31 for a rotatable packing between
a casing and a reciprocating rod. (Lines With Other Classes and
Within This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Pipe Joints or Couplings, appropriate subclasses for joints between pipes,
including tubing and casing sections of general utility. (Lines
With Other Classes and Within This Class, Well Shafts and Methods
and the Like Elsewhere Classified.)

Handling: Hand and Hoist-Line Implements,
subclasses 68.22+ for hoist buckets to be inserted into a well, and
subclasses 65.5 and 86.1+ for grappling devices for withdrawing loose
or stuck objects from a well. Grapples for Class 294 may include
means for washing dirt away from the object to be grappled. Processes
for withdrawing loose or stuck objects from a well involving the
use of grappling devices are classified in appropriate subclasses in
Class 166. The line between hoisting buckets or grapples for Class
294 and receptacles for Class 166 is set forth in Class 166, subclasses
99 and 162. The line between grapples for Class 294 and expansible
anchors for Class 166 is set forth in Class 166, subclass 206. (Lines
With Other Classes and Within This Class, Devices or Processes in
Wells or the Like Elsewhere Classified.)

Mining or In Situ Disintegration of Hard Material, appropriate subclass for recovering hard, solid,
valuable materials from the earth and for utilizing a tunnel (a
horizontal earth passage in which a human works) to recover valuable fluid
material from the earth. Wells and well processes for extracting
fluid from the earth, including petroliferous material such as freely flowing
oil, oil adhered to the formation which must be recovered by secondary
methods, asphalts and tars are classified in Class 166. Furthermore,
wells and well processes for recovering hydrocarbons from material
such as shale by treating the material in situ to remove only liquid
or gas, or for treating or converting solid hydrocarbons such as
coal or lignite in situ for recovery solely as a liquid or gas are classified
in Class 166. However, wells and well processes for treating or
comminuting solid materials other than hydrocarbons (e.g., sulfur
and salt) for recovery in the liquid or gaseous state are classified
in Class 299. Likewise, wells and well processes for recovering valuable
solid material including hydrocarbons such as coal, oil shale or
oil sand, where any of the valuable material is removed from the
well in the solid state, are classified in Class 299. (Lines With
Other Classes and Within This Class, Well Shafts and Methods and
the Like Elsewhere Classified.)

Electricity: Measuring and Testing,
subclasses 323+ for subject matter relating to the determination
of an electrical characteristic of the sub-surface of the earth,
and involving devices in wells. (Lines With Other Classes and Within
This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

Communications: Directive Radio Wave Systems
and Devices (e.g., Radar, Radio Navigation), appropriate subclasses for radar systems in wells.
(Lines With Other Classes and Within This Class, Devices or Processes
in Wells or the Like Elsewhere Classified.)

Communications, Electrical: Acoustic Wave Systems
and Devices,
subclasses 25+ for seismic well logging; subclasses 81+ for
acoustic wellbore telemetering; and subclass 86 for acoustic borehole
testing. (Lines With Other Classes and Within This Class, Devices
or Processes in Wells or the Like Elsewhere Classified.)

Hydraulic and Earth Engineering,
subclass 8for a pressurized caisson; subclass 36 for drainage
systems comprising shafts sunk in the earth for removing surplus
water from the soil; subclass 53 for underground storage of fluids;
subclass 128.15 for the collection of fluid contaminants in a collection
well for the purpose of soil remediation, including a significant
soil treatment step external to the well; subclass 129.4 for the
subterranean disposal of waste in an earthen fracture which is created with
fluid pressure; subclass 129.45 for drainage or collection of waste
or waste byproduct within a waste site for preventing the waste
or waste byproduct from contaminating "clean" neighboring
earth or earthen structure or purging the waste product from the
waste site; subclass 133 for methods and structure relating to shafts
of general utility sunk into the earth, and for methods and apparatus
for the sinking of shafts, including well shafts, by means of a caisson
or other similar means for excavating earth beneath a shaft being
sunk; subclass 232 for a process and apparatus for installing piles in
the earth; subclass 233 for casting a pile of hardenable material
in situ; subclass 234 combined with heating, cooling, or explosion;
subclass 240 combined with withdrawal of a form structure subsequent
to placing the fluent material; subclass 249 for methods and structure relating
to the sinking of a caisson or hollow shaft which is subsequently
filled to form a pile or pier; and subclass 270 for temporary shoring means.
(Lines With Other Classes and Within This Class, Well Shafts, and
Methods and the Like Elsewhere Classified.)

Pumps, for means for pumping liquid out of wells, especially
subclasses 56+ , for drilled well free piston type pumps, subclasses
86 and 118+, for pneumatic displacement pumps, subclasses
90+, and 108+, for aerated column pumps, subclass
358, for a pump-motor unit raised in a well conduit by pressure
fluid applied below the unit, subclass 434, for pumps with a separate
port or noncyclic valve for draining a pump portion, subclasses
448+, for well pumps removable as a unit by drive rod manipulation
and subclasses 451+, for well removable with the pumping
member. (See Lines With Other Classes and Within This Class, Summary
of Well Feature.)

Pumps,
subclasses 63+ for apparatus having (1) signals, indicators, registers,
recorders, or gauges for indicating a condition of the pump or pumped
fluid or the position of a pump part such as a piston, control member,
valve, etc., such devices comprising relatively movable, changeable
or audible information giving parts, or (2) transparent viewing
means whereby the pump operation or the condition of some part thereof
may be observed.

Rotary Expansible Chamber Devices, for rotary expansible chamber devices, per se.
The line between Classes 166 and 418 is the same as that set forth
between Classes 166 and 417 for which see Lines With Other Classes
and Within This Class in the main class definition to Class 166.
(Lines With Other Classes and Within This Class, Devices or Processes
in Wells or the Like Elsewhere Classified.)

Chemical Apparatus and Process Disinfecting, Deodorizing,
Preserving, or Sterilizing,
subclasses 50+ for apparatus for gas sampling involving use of
sorbents or chemical treatments which may include a shaft sunk in
the ground to collect gas for analysis. (Lines With Other Classes
and Within This Class, Well Shafts and Methods and the Like Elsewhere Classified.)

Coating Processes,
subclasses 230+ for processes of Coating the interior of hollow
articles in general. (Lines With Other Classes and Within This
Class, Devices or Processes in Wells or the Like Elsewhere Classified.)

Chemistry: Analytical and Immunological Testing, for processes for gas sampling involving the use
of sorbents or chemical treatments which may include a shaft sunk
in the ground to collect samples. (Lines With Other Classes and
Within This Class, Well Shafts and Methods and the Like Elsewhere
Classified.)

Earth Boring, Well Treating, and Oil Field Chemistry, for processes involving no more than placing specific
compounds or compositions in a well using insignificant manipulative steps.
See Subclass References to the Current Class above for a subclass
Reference to a detailed discussion. (Lines With Other Classes and
Within This Class, Devices or Processes in Wells or the Like Elsewhere
Classified.)

A pipe which lines all or a portion of the wall of a
well. The casing may be adjacent the wall of the well for only a
part of its length and lie within another casing section for the
remainder of its length. The casing usually is of metal and is
used with cement between it and the well wall. The casing is intended
to form the permanent lining of the well.

CENTRAL CHAMBER

A generic term covering both a central conduit, as defined
below, and a receptacle for bodily transport of fluid material from
inside the well to the top of the well or bodily transport of material
from the top of the well for discharge at a point in the well.
In a well device the central chamber is considered to be the primary
locus from which or to which fluid is moved. For example, the "central
chamber" in a tester is the sample chamber receiving the
test fluid, whether this be a receptacle or a tubing, while the "central
chamber" in a liquid discharging washer is the primary
place from which liquid flows, whether this be a tubing or a receptacle.

CENTRAL CONDUIT

Any passage forming conduit which extends from the top
of the well into the well and is positioned within another conduit.
The central conduit may be, for example, a string of tubing positioned
within another tubing or within the casing, or it may be a string
of casing positioned within the well bore.

FLUID

A material capable of flowing. A naturally occurring fluid
in the earth. It includes gases, liquids, plastics, and solids which
can be handled in the manner of a liquid.

LINER

A column of casing having screen forming perforations which
does not extend to the top of the well and which is usually the
lowest column of casing in the well. The liner is placed in position
by lowering it from the top of the well through the casing sections
already placed in well. The perforations may be formed before the
liner is run into the well or after. The liner is sometimes surrounded
by a perforated section of casing, the liner then becoming a secondary
lining section of the well.

TUBING

A pipe for conducting fluids which extends from the top of
the well to some point below and lies within the casing or is used
without a casing as a temporary structure.

WELL CONDUIT

Either (1) a well tubing, (2) a well casing, or (3) the earth
or cementitious wall of the well.

This subclass is indented under the class definition. Devices comprising a main vertical shaft and one or more
conduits extending outwardly transversely into the formation for
collecting fluid therefrom or inserting fluid thereinto.

(1)Note. The transversely extending conduits of this subclass
comprise relatively long tubes. See subclass 100 for a short probing
member carried by a central tube and extending transversely into
the earth.

Mining or In Situ Disintegration of Hard Material,
subclass 19for a mining plan or layout which may comprise
lateral tunnels or drifts large enough for a person to work in extending
outwardly from a vertical shaft.

This subclass is indented under the class definition. Devices comprising means specially adapted for use in the
operation of placing a mass of filter material, e.g., gravel, in
final position in the well.

(1)Note. Means for merely lowering a preformed screen or bed
of filter material into the well is not included. Such filter beds
may have means aiding to form them above ground or a contiguous
reservoir for filter material which is intended to fall down to
replenish the main filter bed. Also means for merely supporting
filter material placed into the well are not included. See subclass
228 for all these devices.

This subclass is indented under the class definition. Devices comprising means to sense a condition which may
or may not be present or may occur spasmodically, and cause operation of
a control device, without the intervention of a human operator,
(e.g., liquid level or specific gravity responsive devices, temperature responsive
devices or self-correlating devices).

(1)Note. For a definition of self-correlating see Class 137,
Fluid Handling, subclasses 87.01+.

(2)Note. Control devices for signals or indicators and control
devices comprising valves or closures across a passage operated
to control fluid flowing in the passage by means sensing the pressure or
velocity of the fluid flowing in said passage and control devices
operated in response to means sensing inertia, gravity, time, the
bottom of the well, an obstruction in the well, a break, projection,
cavity or joint in a well are not considered automatically operated
in this class and are classified on other features.

for well devices with means indicating time or distance
or with counting means or temperature responsive means, the temperature
responsive means sensing temperature as part of an operating cycle
or by insertion into a zone of predetermined temperature which causes
a predetermined response.

and the subclasses there noted for anchor devices
caused to be set by a means sensing a cavity, joint or break in
a wall or caused to be set by an inertia or gravity sensing means,
especially subclasses 209+ for anchors caused to be set
by inertia or gravity sensing means and subclasses 214+ for
anchors caused to be set by means sensing a cavity joint or break
in a well wall.

This subclass is indented under the class definition. Devices comprising a well having plural earth formations
which are isolated from each other so that fluid is separately obtainable therefrom
and in which pumping means, comprising one or more individual pumps,
is operatively associated to pump from each formation for separate
delivery of the fluids from the well.

This subclass is indented under the class definition. Devices comprising means for severing a flexible strand
such as a cable, rope or the like, the severing means being located
in a well below ground level when performing the severing operation.

(1)Note. See (1) Note under subclass 75.1 for the meaning of
ground level as used in this definition.

(2)Note. The cable or rope may be used to suspend a tool, such
as an earth boring bit or the like, and the nominal recitation of
a tool by name will not preclude classification in this subclass.

This subclass is indented under subclass 54.5. Devices comprising a means for causing the operation of
the severing means which requires contact of some part of the device
with a stationary object in the well for its operation, the stationary
object being a member which is held in position in the well by the
flexible strand which is to be severed.

(1)Note. Many of the devices found in the subclasses noted in
the Search Class Notes of subclass 54.5 are of this type.

MEANS FOR PERFORATING, WEAKENING, BENDING OR SEPARATING PIPE
AT AN UNPREPARED POINT:

This subclass is indented under the class definition. Devices comprising means for perforating, weakening, bending
or separating the side wall of a well pipe at a location in the
pipe which has not been specially preconditioned for such action.

(1)Note. A means for merely indicating the location in a pipe
at which an operation such as cutting is to be performed is not considered
a special preconditioning of the pipe.

(2)Note. The earth wall of the well is not considered a "pipe".

(3)Note. A mere pipe coupling sleeve is not a specially preconditioned
location.

(4)Note. A device to fire a bullet or explode a shaped charge
to perforate a casing or other wall member in a bore is classified
in Class 175, even though there is no disclosure that penetration
of the earth occurs.

(5)Note. If the device functions above ground level some significant
limitation to the well art should be present for classification
under this definition, but if the device functions below ground
level a disclosure line prevails, except where there is a body of
art in other classes relating to such devices used in a well.

Metal Deforming, appropriate subclass for a pipe deforming means of general
utility, including a pipe deforming means described as functioning
in a well and particularly
subclasses 112+ for a tool which orbits or rotates as it operates
and subclass 391 for a tool having motion in a fixed path to deform
fixed material.

Boring or Penetrating the Earth,
subclasses 2+ for a device for firing a bullet or exploding a
shaped charge from an inaccessible bore to penetrate the formation
and including such a device even when limited by disclosure to merely
perforating or cutting a casing or other wall member in the bore,
subclasses 249+ for earth boring apparatus with a core
retaining or severing means which is movable relative to a bit and
subclasses 263+ for an earth boring cutter element which
is laterally shifted below ground.

This subclass is indented under subclass 55. Devices including a means for performing a function below
ground level unlike and other than a function which directly contributes
to the use of the device as a perforating, weakening, bending or
separating device.

(1)Note. The means for performing an unlike function comprise,
for example, means to collect a fluid sample, insert an orifice
bushing in a pipe wall, insert treating fluid or cement into the
well or grapple or otherwise remove an object from the well (unless
the grappling or removing means also performs a function which is
necessary to the perforating, weakening, bending or separating operation,
such as grappling in order to activate cutting means, such grappling means
being found in the following subclasses indented under subclass
55).

Boring or Penetrating the Earth,
subclasses 2+ for a device which fires a bullet or explodes a
shaped charge for perforating a wall member in a bore which device
inherently causes penetration of the formation, especially subclass
4.51 for such device which has a position indicating or orienting means
and subclass 4.52 for such device which has a wall engaging packer
or anchor. In accordance with the line between Classes 166 and
175, as set forth in the class definition of Class 175, Lines With
Other Classes and Within This Class, and the definition of Class
175, subclass 2, a claim to an apparatus comprising a gun or shaped
charge perforating means disclosed as inherently functioning to penetrate
the earth is classifiable in Class 175, subclasses 2+ even
if it also recites a disparate well feature. Thus, apparatus patents
of this type are classified as originals in Class 175 and cross-referenced
to Class 166, subclass 55.1 if appropriate while patents of this
type with method claims are classified as originals in Class 166,
subclass 35 and cross-referenced to a suitable apparatus subclass
if appropriate.

This subclass is indented under subclass 55.2. Devices in which the tool is forced or guided into engagement
with the wall of the well pipe by means comprising a member having
an angular or curvilinear surface.

Boring or Penetrating the Earth,
subclasses 79+ for earth boring apparatus in which the tool shaft
is advanced relative to a guide insertable in an inaccessible hole
(e.g., well bore) to change the direction of advance.

This subclass is indented under the class definition. Devices comprising a well screen combined with a pipe located
outside of the screen for handling fluid to clean the screen or
the bed of earth or filter material outside of the screen.

(1)Note. The pipe may be located inside of an outer screen member
so long as it is located outside of an inner screen member.

This subclass is indented under the class definition. Devices for causing a heating, refrigerating or heat insulating
effect.

(1)Note. For classification in this and indented subclasses
the apparatus must be described as purposely intended to perform
the said functions. An apparatus adapted to perform some other
function and causing a mere inherent, unclaimed heating, refrigerating
or insulating effect is not classified in this group of subclasses.
Such apparatus is classified on other features.

(2)Note. The mere use of the earth as an insulating means, (as
when a tunnel is used to inject fluid in a well and the earth above
the tunnel insulates it) is not included. See subclasses 75.11+ (especially
90.1) for such devices.

(3)Note. Where the sole function of an element is described
as for supplying a heating or refrigerating or insulating effect,
classification is in this or indented subclasses even if such function
is not claimed.

(4)Note. A device comprising a heating means used merely to
set off an explosion, the explosion being intended to accomplish
some function due to the violent pressure exerted and not due to heat
is not classified in subclasses 57+. See subclasses 55
and 63 for such devices.

(5)Note. An internal combustion engine, per se, is not considered
a heating means if the only use of the engine is for driving a
shaft or the like.

Boring or Penetrating the Earth,
subclasses 11+ for processes or apparatus for boring by directly
applying heat to fluidize or comminute the earth formation and subclass
17 for processes or apparatus including heating or cooling within
the bore, or heating or cooling the drilling fluid.

This subclass is indented under subclass 57. Devices comprising (1) means for supporting a supply of
fuel in the well or (2) a heated bar or container adapted to be
lowered into the well after it is heated or filled with a hot material.

(1)Note. "Fuel" in this subclass is any material
which is intended to enter into an exothermic chemical reaction
in the well.

This subclass is indented under subclass 57. Devices comprising pump or plunger means in the well for
drawing well fluids out of the well or into a receptacle which is
lifted out of the well.

(1)Note. Devices in which a heated fluid is conveyed into the
well so as to act as both a heating and a lifting means are not considered
to be pumps for this subclass. Such devices may be found in subclass 57.

for explosive or gas generating devices for perforating,
weakening, bending or separating a well pipe at any unprepared point
other than devices for firing a bullet or exploding a shaped charge
which inherently cause penetration of the formation for which see
Class 175, subclasses 2+.

Ammunition and Explosives,
subclasses 301+ for well torpedoes for use in a well to break up
a formation, clean a bore, etc., and for a well torpedo combined
with a plug which acts as a tamping means. Class 166, subclass
63, however, take an explosive surrounded by material to form a
plug when the explosion occurs.

Boring or Penetrating the Earth,
subclasses 2+ for subject matter relating to a device for firing
a bullet or exploding a shaped charge in an inaccessible bore to
penetrate the earth formation or perforate or cut a casing or other
wall member in the bore and inherently penetrate the formation.

WITH TIME OR DISTANCE MEASURING, TEMPERATURE RESPONSIVE
OR COUNTING MEANS:

This subclass is indented under the class definition. Devices combined with means for measuring time or distance,
responding to temperature changes for performing some function,
or counting objects such as joint couplings.

(1)Note. A mere delayed action response to a condition such
as provided by a damper is not considered time measuring. Such
devices are classified on other bases.

(2)Note. Means with indicia to indicate the position of adjustment
of a device such as a valve or telescoping part are not included
in this subclass. Such a means in combination with a well device
would be classifiable in subclass 113.

This subclass is indented under the class definition. Devices comprising means intended to function and remain
above ground level combined with means intended to function in the well
below ground level.

(1)Note. Some specific feature of both the above ground level
and below ground level means must be recited in a claim for classification
of a patent in this or indented subclasses. The mere recitation of
a cable, pipe, rod, tubing or casing for insertion in a bore hole
is not sufficient. Above ground level apparatus combined with such
features will be found in subclasses 75.11+ or in other
subclasses, according to the subject matter involved.

(2)Note. The mere recitation by name only of a pump above ground
for inserting a treating or circulating fluid is not sufficient
for classification of a patent in this or indented subclasses. Such
patents are classified on other characteristics.

(3)Note. See subclass 75.11 for the meaning of ground level
in this definition.

for a well which is above ground but below water.
Note, however, that a well device which is disclosed as being under
water but in which no claim is made to a feature peculiarly adapting
the device to function under water is considered as if the water were
not present and is classifiable in subclasses 67+ if it
otherwise meets the definition of subclass 67.

This subclass is indented under subclass 68. Devices comprising (1) an above ground driving motor for
actuating the below ground pump or plunger, said motor being carried
on a ground embedded casing or an embedded foundation which supports
a casing or (2) an above ground pump means which acts on fluid derived
from the well.

(1)Note. The pump means under part (2) of the above definition
may be a pump for supplying motive fluid to a drive motor for the
below ground pump, the main criteria being that the fluid be derived
from the same well.

This subclass is indented under subclass 67. Devices comprising the combination of an above ground apparatus
and a receptacle for insertion in the well.

(1)Note. The claiming of a magazine other than the casing for
receiving the receptacle, or a means associated with the well for
engaging the receptacle to support or open it is sufficient for
classification in this subclass.

(2)Note. A "receptacle" is a device which discharges
material in the well or receives fluid from the well and transports
its contents between the top of the well and the point of use by
its own bodily movement.

for receptacles to be inserted into the well for
function therein and also having means which descend into the well
with the receptacle but are intended to function only above ground.
An example is a bailing receptacle with a discharge valve which
is intended to be opened only above ground.

Material or Article Handling,
subclasses 403+ for portable receptacle emptying devices, and subclasses 639+ and
657+ for means for lifting well buckets and discharging
their contents outside of the well.

This subclass is indented under subclass 67. Devices comprising (1) above ground apparatus claimed in
combination with a piston as defined in subclass 153 or a mechanical
cleaner as defined in subclass 170, or (2) above ground apparatus
with means for engaging a device to be inserted into the well to
restrain the device against upward or downward movement.

(1)Note. Under (2) of the definition the means for engaging
the device must be something other than a supporting cable, rod
or pipe attached to the device.

(2)Note. The "device" under (2) of the definition
must be something other than a mere tubing, casing, cable or rod
extending into the well from above ground level.

for a sealing means on a casing head for a cable
rod or pipe in combination with means to be engaged by a well device
for causing the sealing means to be released or yield so that the
well device may pass out of the well.

This subclass is indented under the class definition. Device comprising means peculiar to a well; e.g., recitation
of a cable, pipe, rod, tubing or casing for insertion in a bore
hole and intended to function with the means and remain at or above
the surrounding terrain.

(1)Note. For purposes of this subclass ground level is either
(a) the level at which a person may work outside the casing of the
well; this working space being provided either in the open, by a cellar,
or tunnel or (b) the level; e.g., in a trench, at which a laterally
running pipe line for discharging well fluid from or inserting treating
fluid into the well is connected to the well casing.

(2)Note. This subclass includes those means adjacent the defined
level though actually below it.

(3)Note. Devices dropped into or forced down along the length
of the well conduit for functioning inside the conduit, and of a
type usually used below ground level, are excluded even though they may
function above ground level. Such devices are classified on other
features, usually as packers, plugs, pistons or wipers.

(4)Note. A well device which is disclosed as being under water
but in which no claim is made to a feature peculiarly adapting the
device to function under water is considered as if the water were not
present and is classifiable in this subclass.

Brushing, Scrubbing, and General Cleaning,
subclasses 210.1+ and 236.01 for wipers or scrapers applied to well
heads for cleaning pipes, rods, or cable passing to or from the
well with no more of the well casing being claimed than is necessary
to support the wiper or scraper. The wiping or scraping device may
include lateral ports, for the purpose only of disposing of material
removed from an inner member being wiped.

Pipes and Tubular Conduits,
subclasses 89+ for pipes or pipe fittings (including well pipe
and fittings) having closures or plugs, or closures and plugs limited
by structure to use with pipes. Class 138 takes such devices even
if named for use with a well casing but a well feature such as a
lateral port causes classification in Class 166.

Boring or Penetrating the Earth,
subclasses 207+ for earth boring apparatus including above ground
means for handling drilling fluid or cuttings and especially subclasses
209+ for such apparatus in which the means engages the
bore entrance.

Valves and Valve Actuation,
subclasses 1.1+ for blowout preventers of the type comprising plural
relatively movable flow obstructing members controlling flow through
the annular passage between an inner rod or pipe and a surrounding
casing or tubing head and having characteristics which go beyond
a mere packing means. Addition of a lateral port in a casing head
structure for diverting flow from the well is enough to cause classification
in Class 166, but Class 251 takes blowout preventers or other valves
in appropriate subclasses even though the valve is operated by the
well fluid pressure or there are plural valves and broad recitations
of casing or casing head structure.

Seal for a Joint or Juncture,
subclass 31for annular seals or blowout preventers between
an inner cable, rope, rod or pipe and a casing head. Addition of
a well feature such as a port for handling fluid will cause classification
in Class 166. A means for causing fluid to tighten the packing, however,
would be classifiable in Class 277 with the packing.

Pipe Joints or Couplings,
subclasses 123.3+ for joints between concentric pipes. Class 285
takes casing heads with means for sealing inner pipes which are
normally stationary, including means for sealing such inner pipes while
they are being run into the well, and/or means for anchoring
pipes against movement up or down with the anchoring feature comprising more
than a mere pipe coupling resting on a sealing or valve device.
The claiming of a fluid handling feature such as a port or valve
will cause classification in Class 166.

Boring or Penetrating the Earth,
subclasses 207+ for earth boring apparatus including above ground
means for handling drilling fluid or cuttings and especially subclasses
209+ for such apparatus in which the means engages the
bore entrance.

Pipes and Tubular Conduits,
subclasses 89+ for pipes or pipe fittings (including well pipe
and fittings) having closures or plugs, or closures and plugs limited
by structure to use with pipes except for a well feature such as a
lateral port.

This subclass is indented under subclass 75.11. Above ground apparatus whose function is changed (a) by
reassembling all or some of their parts in a different relationship
or (b) by adding or omitting a part.

(1)Note. Since well casing heads are commonly arranged (e.g.,
with threaded bolts) so that parts may be interchanged, added or
omitted, the convertability feature must be explicitly discussed
in the specification and recited in the claim for classification
here.

(2)Note. The mere use of a valve to shut off flow so parts may
be interchanged, without removal of the valve, is not considered
enough for classification in this subclass.

This subclass is indented under subclass 77.1. Moved tubing wherein the thin-walled pipe is pushed by an
assembly including a generally tubular-shaped member confining a
movable mass and driven by fluid pressure.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a separate apparatus for
effecting the make-up or break-up of discrete pieces of thin-walled
pipe or tubular bar in a line being inserted or removed from the
well.

(1)Note. The devices classifiable in this subclass must be specifically
described as performing one of the following functions during the
connecting or disconnecting operation (a) rotate one section of
rod or pipe, (b) hold one section of rod or pipe stationary or (c)
temporarily support a section of rod or pipe.

(2)Note. The separate apparatus under this definition must be
normally separate from the device being assembled or disassembled
and must be something more than a mere detachable section of pipe constituting
a continuation of the line of pipe being handled.

(3)Note. A mere guide for aligning a rod or pipe section to
be connected or disconnected from another without supporting the
section is excluded from this subclass and will be found below in
subclass 85.1.

This subclass is indented under subclass 75.11. Above ground apparatus which prevents the flow of fluid
from or into the well including (a) a device having wheels or skids
or (b) structure arranged to merely rest on the area around the pipe
or be connected to either this area or a foundation only, rather
than to the casing or tubing of the well.

This subclass is indented under subclass 75.11. Above ground apparatus comprising (a) a discrete tubular
member axially shiftable to enable a flow control means; e.g., gate
valve, to stop flow or (b) a hinged plate allowing passage of a
tubular member or bar in one direction and preventing upward flow
after removal of a tubular member or bar.

(1)Note. The axially adjustable member remains assembled with
the rest of the device at all times.

This subclass is indented under subclass 75.11. Above ground apparatus comprising an enclosure or deflecting
member, other than the casing head, placed about a section of well
pipe so that the liquid contents of the pipe may be prevented from
being indiscriminately emitted.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a detachably connected
flow preventing or enclosure device for tubing, pipe, rod, or wireline
within a casing opened by a lug, movable rod, collar, trip member,
or protuberance on the tubing, pipe, rod, or wireline to cause the
device to be detached from the well.

Seal for a Joint or Juncture,
subclasses 5+ for a packing which opens or yields to allow a
projection on the rod to pass, subclasses 19+, for sealing
means with external fluid receiver usually between a casing and
an inner rod, pipe or cable, subclass 31 for rotatable packing for
axially moving rod, subclass 33 for axially biased rod.

This subclass is indented under subclass 82.1. Releasable seal or cleaner in which there are catch or dog
members which move towards the centerline of the casing, when the
projection contacts the device, in order to detach the enclosure
or the flow preventing device.

Seal for a Joint or Juncture,
subclasses 5+ for a packing which opens or yields to allow a
projection on the rod to pass, subclasses 19+, for sealing
means with external fluid receiver usually between a casing and
an inner rod, pipe or cable, subclass 31 for rotatable packing for
axially moving rod, subclass 33 for axially biased rod.

Valves and Valve Actuation,
subclasses 1.1+ for blowout preventers of the type comprising plural
relatively movable flow obstructing members controlling flow through
the annular passage between an inner rod or pipe and a surrounding
casing or tubing head and having characteristics which go beyond
a mere packing means. Addition of a lateral port in a casing head
structure for diverting flow from the well is enough to cause classification
in Class 166, but Class 251 takes blowout preventers or other valves
in appropriate subclasses even though the valve is operated by the
well fluid pressure or even though there are plural valves and broad
recitations of casing or casing head structure.

This subclass is indented under subclass 75.11. Above ground apparatus comprising (a) means for cooperating
with a separate apparatus for aiding in putting together or taking
apart a device or a part thereof or (b) means for aiding in inserting
a member into or removing a member from the well.

(1)Note. The separate apparatus under (a) of the definition
must be normally unconnected with the device being assembled or
disassembled and must be something more than a mere detachable section
of pipe constituting a continuation of the line of pipe being handled.

(2)Note. The aiding means under (b) of the definition must comprise
more than a mere flared section of pipe.

Valves and Valve Actuation,
subclasses 1.1+ for blowout preventers of the type comprising plural
relatively movable flow obstructing members controlling flow through
the annular passage between an inner rod or pipe and a surrounding
casing or tubing head and having characteristics which go beyond
a mere packing means. Addition of a lateral port in a casing head
structure for diverting flow from the well is enough to cause classification
in Class 166, but Class 251 takes blowout preventers or other valves
in appropriate subclasses even though the valve is operated by the
well fluid pressure or even though there are plural valves and broad
recitations of casing or casing head structure.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a flow regulating device
in combination with a means for (a) preventing upward or downward
movement of an inner pipe, rod, or cable member depending into a
well casing or tubing or (b) preventing flow in the annular space
between a casing supported enclosure and a pipe, rod, tubing, or
wireline, said regulating device being disposed either in the well
casing, tubing or pipe or in a conduit communicating with said well
casing, tubing or pipe.

(1)Note. The sealing means under (b) of this definition may
be of the blow out preventer type which is considered a "valve" for
classification in Class 251, subclasses 1.1+.

This subclass is indented under subclass 86.1. Inner member seal with valve wherein the flow regulating
device controls flow through the annulus defined between the pipe,
rod, tubing, or wireline and casing.

This subclass is indented under subclass 86.1. Inner member seal with valve comprising a flow regulating
device which is movable in the direction of the axis of a pipe in
order to control fluid flow in the pipe.

This subclass is indented under subclass 75.11. Above ground apparatus comprising an enclosure having an
opening in a side wall thereof for allowing flow of fluid into the
well or from the well for outside delivery in combination with (a)
means for preventing upward or downward movement of a pipe, rod
or cable member depending into the well or (b) a flow prevention
device closing the annular space between the enclosure and an pipe,
rod or cable member.

(1)Note. The sealing means under (b) of the definition may be
a valve type blow out preventer classifiable, in Class 251, subclasses
1.1+.

Seal for a Joint or Juncture,
subclasses 5+ for a packing which opens or yields to allow a
projection on the rod to pass, subclasses 19+, for sealing
means with external fluid receiver usually between a casing and
an inner rod, pipe, or cable, subclass 31 for rotatable packing
for axially moving rod, subclass 33 for axially biased rod.

This subclass is indented under subclass 88.2. Slip type inner member anchor with lateral port wherein
the flow prevention device and means for preventing movement are
put into mechanical motion simultaneously.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a head, cap, or system
of pipes attached to a well casing or tubing in combination with
a means for regulating the flow of fluid by presenting a predetermined
limitation to fluid movement.

(1)Note. All valves and pipes offer some restriction to flow;
this subclass, however, is intended to take only those well devices
which include means specially built to restrict flow and known to
the art as "chokes" or "beans".

This subclass is indented under subclass 75.11. Above ground apparatus comprising a cover or top plug type
structure in which all, or a section, is hinged to a pipe or to
a tubular member inserted in a well.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a cover or top plug-type
structure for a well casing or tubing which is divided on a longitudinal
plane so that it may be applied in a lateral direction to the casing
or tubing.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a cover or top plug-type
structure for a well casing or tubing which is adjustable for movement
away from or over the tubing or casing in a direction perpendicular
to the longitudinal axis of the tubing or casing.

This subclass is indented under subclass 75.11. Above ground apparatus comprising (a) a head for attachment
to a casing or tubing and having a flow regulating device operating
across a vertical passage in line with the casing or tubing and
an opening for a pipe in the side wall of the head or (b) a cap
for closing off the tubing or casing and an opening for a pipe in
the side wall of the tubing casing or cap.

(1)Note. There must be some detail of the head or cap shown
or claimed for classification in this subclass. A patent having mere
conventional showing of the cap or head and claims drawn to other
features is classifiable in subclass 75.11 or other appropriate
subclasses.

(2)Note. A sole disclosed use as a well casing head of a structure
comprising a valve and a lateral port for handling fluid to or from
the well is enough to cause classification in Class 166.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a head, cap or enclosure
for attachment to a well casing or tubing and structural reinforcement
such as tie rods for holding or shoring the head, cap or enclosure
to the well casing or tubing or for attaching the casing or tubing
to the ground or to a fixed well structure.

(1)Note. The anchoring or bracing means must comprise more than,
or be additional to, a mere pipe joint or joint securing a closure
to the top of a pipe.

This subclass is indented under subclass 75.11. Above ground apparatus comprising a cover or top plug type
structure for attachment to a well tubing or casing in combination
with a flow regulating device contiguous to, or on, the cover, plug-type
structure, tubing, or casing.

(1)Note. There must be some detail of the valve structure or
its attaching means shown for classification in this subclass.

Valves and Valve Actuation,
subclasses 1.1+ for blowout preventers comprising separate sections
operable to close the annulus about a pipe and having characteristics
which go beyond a mere packing means. Provision of a specific means
for coupling the valve to the casing or arrangements of valves in
branch lines are examples of features which will cause classification
of a well casing head structure in Class 166.

This subclass is indented under subclass 75.11. Above ground apparatus including generally coaxial conduits
which (a) are not located one within another and (b) extend from
a position above ground to a position below ground.

This subclass is indented under the class definition. Devices comprising a means which is fixed in position in
the well combined with a means for grappling an object in the well
and a means for lifting the object and moving it relative to the
fixed means.

This subclass is indented under the class definition. Devices adapted to retrieve a plurality of discrete objects
(e.g., pieces of tools usually known as junk or fish from a well).

(1)Note. This subclass is closely related to the well grapple
art in Class 294, Handling: Hand and Hoist-Line Implements, subclasses
86.1+, especially subclass 86.11. The distinction is that
Class 166, subclass 99 relates to junk retrievers which have features
of fluid handling or other well features considered too specialized
for Class 294. Specifically, if junk is swept into the retrieving
device by means of fluid circulated down the inside of a central
conduit which supports the retrieving device classification is in
Class 166, subclass 99. On the other hand, a junk retrieving device
(e.g., a junk basket as in Class 294, subclass 86.11) in which junk
is swept into the basket by circulation of fluid down the outside
of a central conduit supporting the device and then up the inside
of the conduit, or a junk retrieving device in which junk is swept
into the device merely by means such as a plunger causing a sudden
inrush of fluid, is classified in Class 294.

(2)Note. The devices of this subclass are intended to comprise
a unitary means to recover junk only, as distinct from a mass of
fluent material which may incidentally contain junk. Thus a device
for this subclass may consist of a receptacle with a foraminous
bottom which permits the fluent material to drain away as distinct
from a receptacle with a solid bottom which retains fluent material.
Receptacles for recovering a mass of fluent material are found
in Class 166, subclasses 107+ and 162+ and also
in Class 294, Handling: Hand and Hoist-Line Implements, subclasses
68.22+. Receptacles in combination with earth boring means
are found in Class 175, Boring or Penetrating the Earth, subclasses
308+. If a single device has two distinct means, one (of
any type) for recovering junk only and one for recovering a mass
of fluent material of the type classifiable in Class 166, subclasses
107+ or subclasses 162+, classification is in
this subclass.

and 162+, for a receptacle for retrieving
fluent material from a well which material may or may not contain
junk, as distinct from a junk retriever for subclass 99 which may
be a receptacle designed to hold only junk but which receptacle
incidentally may also hold a small amount of fluent material.

Boring or Penetrating the Earth,
subclasses 244+ for a core removing means, which core may contain
junk and subclasses 308+ for earth boring means with a
receptacle which may be adapted to retrieve junk.

Handling: Hand and Hoist-Line Implements,
subclasses 86.1+ for a well grapple, especially subclass 86.11 for
a well grapple of the basket forming type and see (1) Note above; and
subclass 86.34 for a device for freeing a single stuck object from
its environment in a well by a washover or cutover means and retrieving
said object.

This subclass is indented under the class definition. Devices comprising (1) a means pressed against the side
wall of a prepositioned well conduit so as to form a seal around
a port for passage of fluid or (2) a means penetrating the earthen
side wall of the well bore so as to provide a passage for fluid
between a tubular member in the well and the formation.

(1)Note. The port is often formed in a packer sealing means.
Separate packers which, broadly considered, form ports between
them are not included. See subclass 191 and the subclasses there
noted for such devices.

Measuring and Testing,
subclass 152.26for a sealing detail in an apparatus for fluid
flow measuring or fluid analysis combined with sampling wherein
the test is not purely electrical or purely magnetic.

This subclass is indented under the class definition. Devices comprising a packer or plug combined with a pump
or plunger means for exerting outward fluid pressure against the
wall of the surrounding conduit either in the space between a pair
of packer or plug means or in the space beneath the packer or plug
means.

(1)Note. The pump or plunger means must be some device other
than a packer or plug which forms a seal with the surrounding conduit
specified in the definition. See subclass 119 for devices which may
create pressure by the relative movement of packer or plug sealing means.

(2)Note. Cementing and washing devices and other well devices
commonly are associated with a pump (usually at the well top) for
producing pressure beneath a packer. A mere broad or nominal reference
to a pump means is therefore not sufficient for classification in
this subclass. Such devices are classified in appropriate subclasses
on other features.

(3)Note. The pump or plunger means must cause a direct outward
fluid pressure. See subclass 106 for devices in which an eduction
pump while withdrawing liquid may create a condition which causes
outward pressure as defined in subclass 101.

This subclass is indented under the class definition. Devices used below ground level and so designed that (1)
by working on them above ground and reassembling all or some of
their parts, adding or omitting a part or rearranging or adjusting
parts they are changed from devices classifiable in Class 166 to
ones which function as devices classifiable in other classes, or
(2) by working on them above ground and reassembling all or some
of their parts or adding or omitting a part their mode of operation may
be changed.

This subclass is indented under the class definition. Devices combined with a pump or plunger means for drawing
well fluid out of the well or into a receptacle which is to be taken out
of the well.

(1)Note. See the class definition of Class 166 for the line
with Class 417, Pumps.

(2)Note. Well devices such as sampling or cementing means frequently
are provided with means for circulating liquids (e.g., introducing
a liquid to drive out a liquid). Such liquid circulating means are
not considered pumps for this subclass. These devices are classified
on other features, mainly, the arrangement of valves and packers
as in subclasses 142+.

(3)Note. Claims involving merely a pump or pump tubing carrying
an expanding support in a well conduit, or a packer or plug structure
for a pump and claiming the pump by name only or as a pump barrel
are classified on the basis of the supporting or packing structure
rather than in this or indented subclasses, the pump or pump barrel
being treated as a mere pipe or central conduit, according to the
disclosure.

This subclass is indented under subclass 105. Devices including (1) a device for both separating and collecting
sand, earth or other solid impurities from the well fluid which
is being or has been moved by the pump or plunger, or (2) a device
which acts as a means for diverting or deflecting impurities away
from the pump or plunger.

(1)Note. Patents which are disclosed as receptacles for elevating
fluid and which may incidently include some earth material are not
included here but will be found in subclasses 107+ below.

This subclass is indented under subclass 105.1. Devices in which the sediment collecting means is formed
within the same housing which houses the pumping element of a pump such
that the sediment is in effect collected in the pump chamber or
housing.

This subclass is indented under subclass 105. Devices including a device having structure to cause gas
(1) to be separated from the liquid well fluid or (2) to be collected
or confined by the structure.

(1)Note. A packer or packers and a passage, whether valved or
not, is not included under the definition of this subclass, see
subclass 106 below. To be included in this definition there must
be some gas directing structure in addition to the packer.

This subclass is indented under subclass 105.5. Devices in which there is a pump of the type which liquid
is pumped by being displaced or carried by a gas (e.g., jet, aerated
column, etc.), and the gas separating or collecting structure includes
means for directing the gas to the pump to act as a pumping fluid
for the liquid.

This subclass is indented under subclass 105. Devices including packers or plugs as defined in subclass
179.

(1)Note. Claims involving merely a pump carrying a packer or
plug or expanding support and including the pump or pump barrel
by name only are classified on the basis of the packing, plug or
support structure rather than in this subclass, the pump or pump
barrel being treated as a mere pipe unless disclosed as a portion of
a central conduit.

This subclass is indented under subclass 105. Devices comprising a container into which a well fluid is
drawn by the pump or plunger means, the container being lifted bodily
out of the well to transport the fluid to the top of the well.

This subclass is indented under subclass 107. Devices in which a pump or plunger piston is mechanically
connected with a valve at the bottom portion of the container so
as to close the valve when the piston is at the end of its lifting stroke.

This subclass is indented under subclass 107. Devices in which there is an opening through the side wall
of the container below the lowest position of the pump or plunger
piston providing for fluid flow through the opening while the container
is in the well.

(1)Note. The opening must be more than a mere scallop on the
lower edge of the container.

This subclass is indented under subclass 105. Devices comprising a pump having a means for causing a portion
of the well fluid being pumped to flow back into the well to treat
it (e.g., wash it) while the pump is being operated to draw a major
portion of the well fluid out of the well.

Pumps,
subclass 434, for pumps including a separate port or noncyclic valve
for draining a pump portion and subclasses 443+ and 446,
for pumps with a pressure responsive distributor (e.g., check valve)
which may be selectively held open as, for example, to drain the
pump.

This subclass is indented under the class definition. Devices combined with means for other functions than operating,
treating or making a well or a means for perfecting the functions
of operating, treating or making a well, the said means not being
provided for in preceding subclasses.

(1)Note. Operating, treating or making a well is considered
to include, for example, flowing, washing, acidizing, cementing,
and connecting or disconnecting parts in a well. Ancillary subcombination
of such devices such as pumps for forcing fluid into a well or inflating
a packer, clutches, detents, knives or release detents or open closures,
means attachable or detachable in the well, bearings or jars are
not considered subject matter for this subclass. Devices including
these means having been classified in appropriate subclasses according
to the features claimed.

(2)Note. Devices found in this subclass include for example,
cementing plugs with an indicating flare fluid, a well plug with
an indicating ball on a string, a bailer with a means for taking
an impression of lost tools, a washing device with a camera, and
cementing casing shoes with means for testing the casing for fluid
tightness.

(3)Note. While well devices with added special means for testing
for fluid leakage are included, well devices such as packers or
plugs which inherently are capable of use as fluid leakage testers without
modification are not found in this subclass but are classified according to
other features.

(4)Note. It is common in the art and inherent in most devices
to give an indication of the operation of some part by manipulating
a flow controlling means so as to cause a change in pressure. Devices
for giving an indication by a change in pressure are not included
unless some indicia means are claimed, such as a gauge, scale or
pointer.

(5)Note. Many well devices inherently give an indication of
their position, as when expanding anchor means catch on conduit
joints, when they are manipulated to operate valves or when detent
or clutch means are operated. Well devices adapted to indicate an
operation by means such as the position of parts or resistance to
motion are not included in this subclass unless an indicia means such
as a scale or pointer is included.

Measuring and Testing,
subclasses 152.01+ , for apparatus for bore hole studies. Such apparatus
may include a sampling device or other well devices such as packers
in combination with means for bore hole study such as flow meters,
temperature recorders, well pressure indicators, etc., the well devices
being used to perfect the bore hole study means rather than being used
for well functions such as treating the well.

This subclass is indented under the class definition. Devices comprising a packer or plug set in final position
within a surrounding conduit (the setting tool or conduit which
supported the packer or plug during insertion into the surrounding
conduit having been withdrawn) combined with a centrally positioned
longitudinally extending member, other than the aforesaid setting
tool or supporting conduit and not a mere retrieving means for the
packer or plug which is run into the surrounding conduit after the
packer or plug is set.

(1)Note. The centrally positioned longitudinally extending member
must be more than a mere piston, fluid driven into the well or plug,
per se. Usually the centrally positioned member is a central conduit,
receptacle or pump barrel. For a piston, fluid driven into the
well cooperating with another such piston see subclass 153.

This subclass is indented under the class definition. Devices comprising a central conduit or centrally positioned
receptacle in combination with a surrounding conduit, the surrounding conduit
being prepositioned in final position in the earth before the central
conduit or receptacle is associated therewith, there being a means sealing
a portion of the annular space between the central conduit or receptacle
and the surrounding conduit.

(1)Note. For classification in this subclass a patent must claim
the surrounding conduit which may even be the earth wall of the
well, with some particularity. For example, the mere naming of
a conduit or a conduit with a perforation or group of perforations
is not enough, but the recitation of spaced perforations or groups
of perforations is sufficient. A mere functional claiming of a
relationship is not enough. See the search notes for devices having
a particular relationship with a surrounding conduit.

(2)Note. The sealing means of the definition is usually a packer
carried by the central conduit or receptacle.

(3)Note. A broadly recited pump barrel is not considered a central
conduit or receptacle. Devices comprising a pump barrel with a
packer cooperating with a shoulder in a surrounding conduit may be
found in subclasses 195 and 203.

This subclass is indented under the class definition. Devices comprising a receptacle so constructed and arranged
that the receptacle or a part thereof is left in the well and separated from
its lowering means, if any, when performing or after performing
its intended function.

(1)Note. The part left in the well must comprise more than a
mere knock out or frangible closure.

(2)Note. These devices are usually intended to plug the well
by rupturing, breaking up or parting the receptacle while releasing
its contents.

This subclass is indented under the class definition. Devices comprising a means positioned in a well conduit
and adapted to be engaged by an element or member movable in the
well conduit so that the element or member is directed laterally
of the longitudinal axis of the well conduit.

Boring or Penetrating the Earth,
subclass 61for processes of drilling curved or redirected
bores and subclasses 79+ for earth boring devices in which
the tool moves axially relative to means to redirect the tool laterally.

This subclass is indented under subclass 117.5. Devices in which the diverting means is secured in operative
position in the well conduit by means movable relative to the diverting means
and adapted to engage or cause a portion of the diverting means
to engage the wall of the well conduit to prevent either longitudinal
or rotary movement of the diverting means relative to the well conduit.

MEANS ANCHORED AGAINST ROTATION IN ONE CONDUIT SECTION
FOR RELATIVELY ROTATING ANOTHER SECTION:

This subclass is indented under the class definition. Devices comprising a means located below ground level in
a well conduit adapted to cause relative rotary motion between one
section of conduit and another section of conduit also located in
the well, said means including a means movable outwardly to engage
the surrounding well conduit section to prevent rotation of one
portion of the rotating means in the well.

(1)Note. Generally one of the sections of conduit is a pipe
which is stuck in the well bore and held against rotation and the
below ground means is anchored to a separate outer well conduit
and engages only the uppermost section of the stuck section in the
manner of a fishing tool.

This subclass is indented under subclass 118. Devices wherein there are at least two packers or plugs
so arranged that all portions of the sealing part of one are bodily
movable with respect to all portions of the sealing part of the other
while the device is in unitary condition in the well.

This subclass is indented under subclass 118. Devices in which the anchoring means is movable to set or
inset position, all or part of the movement being due to fluid pressure.

(1)Note. The whole of the movement to operative locking position
is usually due to the fluid pressure. Devices in which some of
the movement to final locking position is due to some other motive power
are classifiable here only if there is also some added modification
of the device for the use of fluid pressure to move or tend to move
the anchoring means. The added modification must be supplementary
to the common placement of a packer and expanding anchor whereby
the pressure of the fluid being blocked acts to increase the anchoring effect.
See subclass 140 for devices so arranged that fluid pressure increases
the anchoring action but having no special modification for this
purpose.

(2)Note. Devices in which fluid pressure is used to release
a latch so that some other means may move the anchoring means are
not classified in this or indented subclasses. See subclass 136
for spring set anchors with latches released by fluid pressure.

(3)Note. The fluid pressure may be caused by movement of the
device through or into a body of fluid.

This subclass is indented under subclass 118. Devices comprising means for detachably coupling the device
to a means for lowering the device into the surrounding conduit,
the detachable connection being such that the packer or plug may
be left in the well while the lowering means is completely withdrawn.

This subclass is indented under subclass 123. Devices in which the connection comprises a latching member
which is movable in a direction generally radially of the well bore
in order to unmake the connection in the well.

This subclass is indented under subclass 118. Devices with a controllable passage between a central chamber
comprising a central conduit or a receptacle and a space below a
packer, as set forth in subclass 142.

This subclass is indented under subclass 126. Devices in which the valve, closure or changeable restriction
controlling the passage is opened, closed or held in position or
freed for movement because the central chamber is moved.

This subclass is indented under subclass 118. Devices wherein the packer is adapted to be supported by
a central conduit from the top of the well as it is run into the
well and there is a fluid passage within the packer but not in communication
with the central conduit passageway in the region of the packer,
which fluid passage connects the space below the packer with the
annular space above the packer, the fluid passage being controllable
by a valve, closure or changeable restriction.

This subclass is indented under subclass 129. Devices wherein the packer blocking portion is expanded
laterally by means of force transmitted through coacting shoulder
members which are situated above the packer and which act to close
the fluid passage as they expand the packer blocking portion.

This subclass is indented under subclass 118. Devices wherein there is a fluid passage between a central
conduit which supports the packer or plug from the top of the well
while it is being run into the well and the annular space above
the packer or plug, between the central conduit and the surrounding
conduit, the passage being controllable by a valve, closure or changeable
restriction.

This subclass is indented under subclass 118. Devices in which there is a fluid passage through the packer
connecting the space below the packer with the space above the packer,
the passageway being controllable by a valve, closure or changeable
restriction.

This subclass is indented under subclass 118. Devices in which the expanding anchor comprises two distinct
means, one being adapted to anchor the device against downward movement,
and the other adapted to anchor the device against upward movement.

This subclass is indented under subclass 118. Devices in which there is a friction means as defined in
subclass 241 and a wedge or cam means engageable with the anchor
means in order to move it outwardly.

(1)Note. The friction means may be identical with the anchor
means if the device is constructed so that the anchor frictionally
resists movement when in the unexpanded condition in order to enable setting
of the device.

(2)Note. The friction means may be a packer or plug sealing
means if this sealing means is used like a friction drag to set
the anchor.

for packers or plugs and expanding anchors set by
fluid pressure wherein fluid pressure acting on a cup type packer
seal may cause it to act in a manner similar to a friction drag
when setting the expanding anchor.

This subclass is indented under subclass 138. Devices wherein the anchoring means is positioned above
the packer or plug blocking portion.

(1)Note. This subclass does not include those devices in which
the anchoring means is positioned in the same zone as the packer
or plug means so that only part of the blocking portion of the packer or
plug is below the anchor. See subclasses 138 and 139 for such devices.

This subclass is indented under subclass 179. Devices comprising an expansible packer or plug in which
the blocking or sealing portion of the packer closes a port in the
side wall of the central tubular member when in unexpanded condition
and opens the port to the space outside the packer or plug when
expanded laterally to blocking position.

(1)Note. A ring portion which is attached to the sealing part
and handled as a unit therewith is considered part of the sealing
portion.

This subclass is indented under subclass 179. Devices comprising (1) a packer constructed to be supported
from the top of the well by a central conduit for insertion thereby
into the well or (2) a packer as defined in subclass 179 for use
with a centrally positioned receptacle as defined in subclass 162,
there being a fluid passage between the central conduit or receptacle and
the space below the packer outside of the conduit or receptacle,
fluid flow through said passage being capable of being altered or affected
by a valve, closure device or changeable restriction in subclass
224 positioned across the passage.

(1)Note. The passage may include as a part thereof any space
inside of the surrounding conduit which receives the packer.

(2)Note. A packer is considered to bound a space even if unexpanded.

(3)Note. The central conduit or receptacle forms a central chamber
for the purpose of receiving or discharging fluid, as for example,
in sampling, cementing or washing devices.

This subclass is indented under subclass 142. Devices in which the central conduit is adapted to be readily
detachable from the packer while in the well by means of a connection
such that either the packer or conduit may be left in the well while
the other member is completely withdrawn from the well.

This subclass is indented under subclass 143. Devices in which the central chamber is a central conduit
and is detachably attached to the lower portion of a casing or screen
section which carries the packer sealing portion so that the central
conduit supports the casing or screen section against the action
of gravity while it is being lowered into the well.

This subclass is indented under subclass 142. Devices in which there is a bypass around the packer and
a valve or closure for the bypass, the control element for the passage
being so interconnected with the valve or closure for the bypass
that complete opening of the passage to upward fluid flow into the
central chamber and closing of the bypass to upward fluid flow are constrained
to occur together.

(1)Note. A bypass is a passage through the packer that connects
the annular space outside the central conduit or receptacle and
above the packer with the space below the packer.

(2)Note. The closing of the bypass and opening of the passage
need not occur exactly simultaneously but may occur a short time
interval apart as the result of an operating movement which is intended
to take place without interruption once started.

This subclass is indented under subclass 142. Devices in which the passage connects with a space below
a plurality of packer blocking means and there is a passageway which
is always open to passage of fluid in either direction between the
central conduit of receptacle and the annular space between the
packer blocking means.

This subclass is indented under subclass 142. Devices in which there is a check valve normally effectively
closing the passage against upward flow of fluid while the device
is being run into the well but permitting downward flow and there
is also a means for rendering the check valve ineffective to stop
upward flow after the device is positioned in the well, either by
opening said valve or providing a fluid passageway around said valve.

This subclass is indented under subclass 142. Devices in which there is also a passageway between the
central conduit or receptacle and the annular space above the packer
and outside of the central conduit or receptacle.

(1)Note. The central chamber may comprise concentric conduits
each of which forms a "chamber", one having a
passage to the space beneath the packer and one having a passageway
to the space above the packer.

for devices as in subclass 149 comprising a passageway
provided between a central chamber and the space above the packer
due to the disconnection of the central chamber from the packer,
or a passageway provided between a setting tool and a concentric
screen section carrying a packer.

This subclass is indented under subclass 149. Devices in which fluid flow through the passageway between
the central conduit or receptacle and the space above the packer
is controllable by a valve, openable closure or changeable restriction
operated or held in position by movement of the central conduit
or receptacle.

This subclass is indented under subclass 149. Devices in which fluid flow through the passageway between
the central conduit or receptacle and the space above the packer
is controllable by a valve, openable closure or changeable restriction
which is responsive to fluid pressure exerted directly upon it
by contact with the fluid whose flow is being controlled.

(1)Note. A valve, closure or changeable restriction operated
by a dropped ball or other means acted on by fluid pressure is not
considered within the definition of this subclass. See subclass
149 for such devices used to control the passageway between the
central chamber and the space above the packer.

This subclass is indented under subclass 142. Devices in which the valve, closure or changeable restriction
controlling the passage is opened, closed, held in position or freed
for movement because the central conduit or receptacle is moved.

for devices having a controllable passage between
a central chamber and a space below a packer and also having a space
below a packer and also having a passageway between a central chamber
and the space above the packer in which the passageway is controlled
by a valve, closure or changeable restriction operated by movement
of the central chamber.

This subclass is indented under the class definition. Devices comprising piston means adapted to be inserted from
the top of the well into an already placed well conduit and to be driven
down by fluid pressure acting directly on the piston.

(1)Note. The piston must closely contact the wall of the casing
or tubing as it moves down or be close enough to function as a scraper.

This subclass is indented under subclass 153. Devices in which a valve, closure or restriction means carried
by the casing or tubing in which the piston operates is opened or
released for opening by engagement of the piston with the means
or an element connected thereto.

This subclass is indented under subclass 153. Devices which are so constructed that fluid may flow downwardly
past the piston at a certain period of its operation by a flexing
of the piston sealing means or opening of a valve or closure.

(1)Note. Plugs which are constructed to be drilled out in their
entirety are not classified in this subclass but will be found in subclass
153 or other indented subclasses.

This subclass is indented under the class definition. Devices comprising a conduit comprising a screen in combination
with a means at the end of the conduit comprising a structure having
a port for conducting fluid outwardly of the end of the conduit
usually to wash the screen.

This subclass is indented under subclass 157. Devices in which there is a separate pipe associated with
the screen for passing fluid downwardly into the well to wash the
screen, the separate pipe being readily removable from association
with the screen structure while the screen remains in the well.

(1)Note. Wash pipes which are disclosed as merely liftable from
the screen structure (e.g., the back pressure valve) are classified
in this subclass if they are also disclosed as capable of being
completely removed from the well leaving the screen in the well.

This subclass is indented under the class definition. Devices comprising a container which is bodily movable for
transporting material from the top of the well and discharging the
material therefrom at a point in the well or which is bodily movable
for receiving fluid material from the well and transporting it to
the well top.

Measuring and Testing,
subclasses 152.23+ for sampling of a well fluid combined with flow
measuring or fluid analysis wherein the test is not purely electrical
or purely magnetic, and especially subclass 152.28 for sampling
of a well fluid combined with fluid flow measuring or fluid analysis
by use of a downhole measuring apparatus wherein the test is not
purely electrical or purely magnetic and subclass 864.51 for receptacles
for taking liquid samples from locations other than wells. See the class
definition of Class 166 for the line with Class 73 as to receptacles used
in a well.

Boring or Penetrating the Earth,
subclasses 308+ , and the search there noted, for earth boring means
with a receptacle for cuttings or sediment. A mere dart extension
to operate a bottom valve is not considered an earth boring means
sufficient for classification in Class 175.

Handling: Hand and Hoist-Line Implements,
subclasses 68.22+ for hoisting bucket or bailer type receptacles,
and subclass 86.11 for devices similar to receptacles for carrying only
solid objects such as junk out of a well. Class 294 takes dumping
and bailing receptacles which are structurally very similar to those
of Class 166, the line being that Class 166 takes those receptacles
that have some feature special to use in wells or are described
for use in wells and are long and slender so as to adapt them for
use in narrow diameter bored wells and also have at least one of
the following features; a pump or plunger means for loading the
receptacle, disclosure that the receptacle or part thereof is left
in the well and separated from its lowering means, a separate air,
gas or vacuum chamber, a valve and destroyable closure, a closed
or valved top, valve control means operated by contact with the
side wall, a bottom loading valve, which is bodily movable for discharge,
a side opening for use in the well. These features form the subject
matter of subclasses 107, 117 and 163 through 169 of Class 166.

This subclass is indented under subclass 162. Devices in which the container has a fluid retaining chamber
and a separate air, gas or vacuum chamber, so arranged that when
a passage into the air, gas or vacuum chamber is opened the fluid
in the well rushes into the fluid retaining chamber.

This subclass is indented under subclass 162. Devices in which there is a closure which is adapted to
be broken or otherwise destroyed so that fluid in the well will
enter the container and there is also a valve for retaining the
fluid in the container.

This subclass is indented under subclass 162. Devices comprising a valve or closure and control means
for the valve or closure adapted to contact the wall of the well
conduit within which the container is positioned.

for devices as defined in subclass 166 in which
there is also a packer, a bypass around the packer and a passage
between the receptacle and the space below the packer which is opened
when the bypass is closed.

This subclass is indented under subclass 162. Devices in which there is a valve across the bottom of the
container to admit and thereafter retain fluid from the well and
there is also an additional valve or openable closure in the side wall
of the container for releasing the contents of the container after
the container is withdrawn from the well.

This subclass is indented under subclass 162. Devices in which there is a valve across the bottom of the
container for admitting and retaining fluid from the well, the valve
and container being so constructed that the valve may be readily
bodily moved from its position across the container so that the
container may be emptied after it has been withdrawn from the well.

(1)Note. In the case of a pivoted valve the "bodily
movement" is such as to include movement of the pivot axis.

(2)Note. A reciprocating type check valve readily movable only
by means extending through the discharge opening is not included
in the definition of this subclass. See Class 294, subclass 72
for such devices.

This subclass is indented under subclass 162. Devices in which there is an opening in the side wall of
the container so that fluid may be discharged from or may enter
laterally into the container while it is in the well.

(1)Note. Usually the lateral port is controlled by a valve member
operated when a part contacts the well bottom.

(2)Note. The opening must be more than a mere scallop on the
lower edge of the container.

Brushing, Scrubbing, and General Cleaning, appropriate subclasses, especially
subclasses 104.05+ for devices of general utility for cleaning pipes
and subclass 249 for flue cleaners. Where the sole disclosure or claimed
use of a cleaner is a use inside a well, classification is in Class
166.

Pumps,
subclasses 545+ , for well swabs (valved pistons reciprocated in a
well to remove fluid therefrom). Well swabs classifiable in Class
417 may include scrapers. Such patents should be cross-referenced
to Class 166.

This subclass is indented under subclass 170. Devices comprising means specially adapted for cleaning
perforations in well conduits.

(1)Note. These devices either comprise means disclosed as entering
the perforations of a well conduit, means claimed in combination
with a perforated conduit or means claimed as adapted to be used
for cleaning perforated conduits. Cleaners which may be used for
perforation cleaning but do not qualify under this note may be found
in subclass 170 or indented subclasses other than subclass 171.

This subclass is indented under subclass 170. Devices comprising a cleaning element so constructed that
its effective lateral dimensions may be reduced while it is being
lowered into a well conduit so that the cleaner may be easily inserted
in the well and then may expand to perform its cleaning function.

(1)Note. The reduction of lateral dimensions must be more than
that brought about merely by the resilience of a bristle or wire
as it is lowered in the well.

This subclass is indented under subclass 170. Devices comprising a cleaning element which can reciprocate
longitudinally of the well relative to a centrally positioned member
extending down into the well from the top of the well.

(1)Note. Usually the cleaning element is mounted loosely on
a rod so that as the rod is reciprocated in the well the position
of the cleaning element varies with respect to the rod.

Boring or Penetrating the Earth,
subclass 1for processes or apparatus for boring the earth
combined with seismic shock generation and subclass 56 for processes
or apparatus for boring the earth including a relationship between
the natural vibration characteristics of one boring element and
(a) the natural vibration characteristics of another boring element
or (b) the frequency of an imposed motion.

This subclass is indented under the class definition. Apparatus having a means for cleaning the interior surface
of a tubular well member.

(1)Note. For classification in this subclass as a wiper, a device
must clearly be intended to function as removing detritus. An incidental
wiping action of a device intended for some other use, such as a
packer or plug, is not sufficient to cause classification here.
Classification is then based on the other use or the characteristics
of the packer or plug.

This subclass is indented under the class definition. Apparatus comprising specific structure for agitating, vibrating
or mixing a slurry used to fix or adhere a pipe to a formation or
to another pipe in a well.

for devices for giving a discrete blow to a well
apparatus or part thereof to free it from the well, any vibratory effect
being merely incidental to the intended function rather than the
principal intended function of the device.

Boring or Penetrating the Earth,
subclass 56for processes or apparatus for boring the earth
including a relationship between the natural vibration characteristics
of one boring element and (a) the natural vibration characteristics
of another boring element or (b) the frequency of an imposed motion.

for devices for giving a discrete blow to a well
apparatus or part thereof to free it from the well, any vibratory effect
being merely incidental to the intended function rather than the
principal intended function of the device.

Tool Driving or Impacting,
subclasses 90+ , for above or below ground impacting devices (other
than lost motion connections in an earth bore) of general utility
for imparting blows to a tool or the like.

Boring or Penetrating the Earth,
subclasses 293+ for below ground hammer or impact members, either
(1) claiming a specific earth cutting means or having some feature
related to earth boring such as a wall engaging guide or packer
on a shaft being used in a boring operation or (2) comprising a
lost motion connection.

This subclass is indented under the class definition. Devices insertable from the top of or well into a well conduit
and comprising: (1) Means usually known as a packer and comprising
a vertical or longitudinally extending tubular member forming a
fluid passage and an annular means projecting from the member and
blocking fluid flow either up or down or both in the annular space
between the tubular member and the surrounding well conduit, said
means comprising structure which goes beyond a mere packing assembly
or (2) means usually known as a plug and comprising a means for
blocking the flow of fluid either up or down or both in a surrounding
well conduit by filling the bore of the conduit.

(1)Note. The device must be insertable from the top of the well
to final position in the well, and the surrounding conduit must
have been finally positioned in the well before the device is inserted
in it. Parts of the device may be inserted at different times in
order to be assembled in the well.

(2)Note. The device may be arranged to stop flow in the annular
space between a pipe and an enclosing conduit by contacting the
top of a shoulder (e.g., a rat hole shoulder) in the conduit. The
shoulder may be disclosed as a flat well bottom, if a sealing function
is clearly disclosed.

(3)Note. An annular casing or tubing shoe is considered to be
a packer for this and indented subclasses only if it is disclosed as
having a blocking function, and the blocking function is claimed,
or if it is specially modified to have a blocking function and the
modification is claimed.

(4)Note. The device must be of limited extent longitudinally
of the well. For example, a filling of concrete extending along
distance between concentric pipes is a part of the pipe structure
rather than a packer.

(5)Note. A packer or plug usually comprises an annular deformable
or laterally expansible blocking or sealing portion, such as rubber,
combined with a supporting structure, such sealing portion and support
structure, per se, being subject matter for Class 277, Seal for
a Joint or Juncture.

(6)Note. The device usually forms a tight seal with the conduit,
but if a device is disclosed as intended to function to block fluid
flow the seal may not be tight.

(7)Note. A brushing or scraping means is not considered a packer
or plug device for this or indented subclasses. See subclass 170
for such devices.

(8)Note. Devices usually called "cement baskets" are
considered to be "packers" for this or indented
subclasses.

Seal for a Joint or Juncture, for a packing element, per se, or material combined
with the structure necessary to cooperate therewith to perform a packing
function, which structure may include a tubular member supporting
an annular means for blocking fluid flow and all the ancillary means for
causing the annular means to function to block the flow, as well
as the surrounding conduit, but does not include a well feature
for a distinct function, e.g., a lateral port on the tubular member
above or below the packing, or structural detail of the tubular
member not contributing to the blocking function. The mere naming
of the device as a well packer or as for use in a well does not
preclude classification in Class 277.

This subclass is indented under subclass 179. Devices comprising a laterally expansible blocking portion
(1) intended to be positioned around and form a seal with a fluid
conducting pipe which is already in place in the well or (2) which
is so constructed that it may be expanded and contracted in the
well to form a seal between the surrounding conduit and an inner
concentric fluid conducting pipe at different positions along the
pipe.

This subclass is indented under subclass 179. Devices comprising means for detachably coupling the device
to a means for lowering the device into the surrounding conduit,
the detachable connection being such that the packer or plug may
be left in the well while the lowering means is completely withdrawn.

This subclass is indented under subclass 181. Devices in which the sealing portion of the packer or plug
is maintained in laterally expanded condition after the setting
means is detached by a ratchet, dog or latch other than an expanding
anchor as defined in subclass 206.

This subclass is indented under subclass 179. Devices wherein the packer is adapted to be supported by
a central conduit from the top of the well while it is being run
into the well, the central conduit extending through the region
of the blocking portion of the packer, and there is a fluid passage
separate from the central conduit passageway, and through the packer blocking
portion which fluid passage connects the space below the packer
with the annular space above the packer, fluid flow in the passage
being controllable or changeable by a valve, closure or changeable
restriction as defined in subclass 224.

for devices with a controllable passage between
a central chamber and a space below a packer or plug and also a
passageway between the central chamber and a space above the packer or
plug, the said passageway being outside the central chamber and through
the packer or plug.

This subclass is indented under subclass 179. Devices comprising a packer or plug adapted to be supported
from the top of the well by a central conduit for insertion thereby
into the well and a fluid passage between said central conduit and
the annular space above the packer or plug between the central conduit
and the surrounding conduit, fluid flow in the passage being controllable
or changeable by a valve, a closure or a changeable restriction,
as defined in subclass 224.

and 183, for a central conduit with a packer, the
conduit passage being continued past the packer blocking means and
there being a controllable bypass through the packer outside of the
central conduit passage.

This subclass is indented under subclass 179. Devices comprising a packer or plug adapted to be supported
from the top of the well by a central conduit for insertion thereby
into the well, and a port for the passage of fluid between said central
conduit and the space outside the conduit adjacent the packer or
plug.

(1)Note. The port may be any side opening or a restricted open
end portion of the central conduit.

This subclass is indented under subclass 185. Devices in which the port is between spaced packer or plug
blocking or sealing means and there is a bypass passage across both
spaced means connecting the spaces outside the central conduit with
each other.

This subclass is indented under subclass 179. Devices wherein the packer or plug is moved into expanded,
blocking position by means of or with the help of fluid supplied
from a central conduit or receptacle or forced into the packer or
plug by a pump or plunger means, the fluid while expanding the packer
or plug being confined within the device.

(1)Note. Operation of a latch by fluid pressure whereby the
packer or plug may be expanded by other means is not included.
Such devices are classified on other features.

for devices in which fluid pressure on a cup shaped
packer expands it and causes it to act on an anchor to cause expansion
thereof, the fluid while expanding the packer or plug not being
confined within the device.

This subclass is indented under subclass 179. Devices comprising a fluid passage through the packer with
a valve, closure or changeable restriction for controlling or altering
flow through the passage.

This subclass is indented under subclass 179. Devices in which the packer or plug seals the space between
the surrounding conduit and two longitudinally extending members
which are positioned in side by side relationship (not one within
the other).

(1)Note. These devices are usually packings for a pump tube
and a gas vent pipe. Where more structure is involved than a mere
packing such a device is classifiable in Class 417 as a pump venting means.

This subclass is indented under subclass 179. Devices comprising means for blocking the flow of fluid
either up or down or both in a surrounding well conduit by completely
filling the bore of the conduit.

(1)Note. The essential elements for filling the bore should
be claimed. For example, if a central support member for a deformable
seal is disclosed as a solid rod and the support member is claimed classification
is in this subclass. However, if a central support member is disclosed
as a pipe which is closed off at one end with a deformable or other
sealing portion claimed, classification is based on other characteristics
of the device if subclasses are provided for such characteristics
since the device as claimed is indistinguishable from a packer.

(2)Note. The plug member as a whole may be adapted to be drilled
up or otherwise destroyed. If only a central portion is destroyed
or is intended to be destroyed first the device is classifiable
in subclass 188.

This subclass is indented under subclass 192. Devices comprising an element which does not closely contact
the conduit wall and is intended to be dropped or floated down the
surrounding conduit (rather than let down by a supporting string)
till it strikes a shoulder on the conduit.

This subclass is indented under subclass 193. Devices comprising a sleeve portion which is moved by the
plug or is moved due to fluid pressure or other means made effective
by the presence of the plug, the sleeve portion being carried by
the surrounding conduit and acting to open or close ports in the
conduit walls for fluid passage.

This subclass is indented under subclass 179. Devices in which the expansible portion is made of a deformable
nonmetallic or soft metallic material and is adapted to engage an inwardly
projecting shoulder on the surrounding conduit.

This subclass is indented under subclass 179. Devices comprising either (1) a central support for the
deformable sealing portion comprising telescoping sections whereby
relative longitudinal movement of this section causes expansion
of the sealing portion or (2) a central support for the deformable
sealing portion having projecting portions relatively movable towards
each other to cause expansion of the sealing portion.

(1)Note. The central support is usually a pipe which extends
beyond the ends of the deformable sealing portion in a longitudinal
direction.

This subclass is indented under subclass 179. Devices in which the laterally expansible blocking portion
of the device has one end thereof attached to and adjacent to a
central pipe support and the other longitudinally displaced end
portion spaced from the support axis and in which the blocking portion
is flexible or hinged to the support whereby the fluid pressure
of the fluid, the flow of which is being stopped, tends to cause
the spaced end portion to engage the enclosing conduit more tightly.

This subclass is indented under the class definition. Devices comprising a screen combined with (1) a valve, closure
or changeable restrictor as defined in subclass 224, (2) a destroyable portion
or (3) a screen part removable from the well while the screen remains
in the well.

This subclass is indented under the class definition. Devices comprising (1) a means attached to a member which
is run into a well conduit already in fixed position in the well,
the means being movable outwardly to engage and jam against the
surrounding conduit wall or to interlock in a preformed recess in
the conduit, the means functioning to attach the member to the conduit
in the well so as to resist action of gravity or a lifting force
or (2) a section of casing which is expansible in the well.

(1)Note. The outwardly movable means usually have teeth that
bite into the surrounding conduit wall and serve to fix the device
in the well conduit.

for devices which frictionally engage or press against
the wall of a surrounding conduit and offer some resistance to longitudinal
movement but are not interlocked with or jammed against the wall
of the conduit to form an anchor.

Handling: Hand and Hoist-Line Implements,
subclasses 86.24+ for internally expanding well grapples, and subclasses
93+ for internally expanding grapples of general utility.
Sole disclosure of, or a statement in a claim of use as a grapple
is enough for classification Class 294.

Pumps, appropriate subclasses for well pumps with expanding
anchor means where there is only a nominal recitation of a pump,
pump barrel or tubing in a claim to a device including an expanding
anchor classification is in Class 166 in this or indented subclasses.

This subclass is indented under subclass 206. Devices in which setting the outwardly movable means by
engagement with an element that forces the outwardly movable means
into contact with the surrounding conduit during running in the
member by a quick downward motion of the member, no other motion
or act of an attendant being required for movement of the outwardly
movable means to the final position and the outwardly movable means
being anchorable to the surrounding conduit at any point thereon.

This subclass is indented under subclass 209. Devices which comprise a friction means with the outwardly
movable means shiftable to the final position after or during a
turning movement of the running in member, so that the outwardly
movable means may be anchored either by a quick downward movement
of the running in member or also may be anchored after or during
a turning movement of the running in member.

Boring or Penetrating the Earth,
subclass 99for a below ground drive motor for an earth boring
apparatus which is anchored to the bore wall by a fluid operated
expansible anchor, and subclasses 267+ for laterally shiftable
cutter elements which are shifted by fluid pressure.

This subclass is indented under subclass 214. Devices in which the spring causes relative movement between
an element that forces the outwardly movable means into contact
with the surrounding conduit and the outwardly movable means to
shift the means radially.

This subclass is indented under subclass 206. Devices in which the outwardly movable means is translated
radially due to relative movement between it and an element that forces
the outwardly movable means into contact with the surrounding conduit
surface.

This subclass is indented under the class definition. Devices comprising means for directing fluid outwardly into
the well from a tubing or casing, said means comprising more than
a mere opening in a wall and (1) acting to give a whirling or tangential
motion to the fluid, or (2) positioned in a side wall of the tubing
or casing rather than being an end opening, or (3) said means being
capable of being projected from the tubing or casing.

Rotary Expansible Chamber Devices, for rotary expansible chamber type pumps or motors,
per se. As between Classes 166 and 210 a patent is placed in Class
166 if its sole disclosed or claimed use is merely as a well screen or
well filter for earth fluids, whether disclosed on a casing or tubing.
Class 210, however, takes patents for filters or screens of general
utility and also those specifically disclosed as pump or pipe intakes
positioned within a well and not forming a casing of the well.

Stock Material or Miscellaneous Articles,
subclasses 131+ for a stock material product in the form of a single
or plural layer web or sheet in which at least one component is
perforated or reticulated, and subclasses 304.4+ for a
composite web or sheet product in which one component is porous
or cellular.

This subclass is indented under subclass 227. Devices comprising an element of limited extent such as
a plug having a straining opening or openings and positioned at
least partially within a hole or recess in a conduit wall.

This subclass is indented under subclass 227. Devices comprising a helically wound element which provides
straining openings between turns of the element, or (2) has straining
openings provided in it or (3) provides straining opening between
itself and a base member to which it is secured.

This subclass is indented under subclass 231. Devices in which the helical element is provided with spaced
lugs to engage an adjacent turn of the element in order to position
the turns to form straining openings.

(1)Note. The spaced lugs may be formed by spaced recesses in
the edge of the helical element.

This subclass is indented under subclass 231. Devices combined with a pipe having solid walls formed with
perforations cooperating with the straining openings of the helical
element to pass the strained fluid.

(1)Note. A skeleton structure built in the shape of a pipe is
not considered a solid pipe with perforations. See subclasses 231
and 232 for such structure.

This subclass is indented under subclass 227. Devices comprising elongated solid elements which provide
(1) straining openings between each other, or (2) straining openings
between themselves and a base member to which they are secured,
or (3) straining openings in themselves.

(1)Note. The elongated solid element may be curved but is not
a complete annulus. However, several separate elongated elements
may be welded or otherwise secured together to form an annular unit.

Stock Material or Miscellaneous Articles,
subclasses 105+ for a stock material product in the form of a composite
sheet or web including layers of angularly related strips or strands (e.g.,
rods, filaments, etc.).

This subclass is indented under subclass 227. Devices comprising a vertically aligned assembly of annular
units which provide straining openings between themselves or at
least two of which have straining openings in themselves.

This subclass is indented under the class definition. Devices comprising means for preventing relative movement
between two parts and manipulable to permit relative movement, or means
to permit relative movement and manipulable to prevent relative
movement, the change in condition between movement prevention and
movement permission being for the purpose of enabling operation
of some device in a well (e.g., setting a packer) and the two parts
always remaining connected in the well by other means.

(1)Note. Devices which include mere end stops to limit motion
are not included in this subclass. See subclass 241.1 for centering
devices which include stops for limiting the sliding movement of
the centering means on their supports.

This subclass is indented under subclass 237. Devices in which the movement prevention means extends completely
across a well conduit but permits fluid to flow past the means, the
means acting to control relative movement between the conduit and
another part.

(1)Note. A separate movable part, such as a go-devil, between
two detent means is not considered within the definition of this
subclass. See other subclasses in this group for such devices.

This subclass is indented under subclass 237. Devices comprising a lug on one part moveable in a branched
slot having a continuous perimeter on the other part, so that though
the lug is always in the slot, movement of the parts (at least in
some directions) is prevented in one position of the lug and permitted
in another position.

This subclass is indented under the class definition. Apparatus comprising positioning means attached to and projecting
laterally beyond (1) a tool; (2) a fluid moving structure; or (3)
a fluid conveying means (i.e., tubing) to centralize within the
well the tool, fluid moving structure, or fluid conveying means.

(1)Note. Included are centralizing means that press against
the inner wall of the conduit to form a stationary point of reference
for manipulation of the well device, but may be moved longitudinally with
respect to the well if enough force is applied.

(2)Note. Included in this subclass are devices for centrally
positioning a casing during a cementing operation.

(3)Note. Included in this subclass are discreet guides for either
connecting (1) two spaced well devices or fluid conveying portions,
or (2) terminating either the device or fluid conveying means, and which
require the well device or fluid conveying means to be fabricated
for the purpose of holding the guide.

for an anchoring device which is jammed against
the wall of a surrounding conduit or interlock therewith, especially
subclasses 210 and 216 for anchoring devices with wedges and friction
drags and subclass 213 for anchors similar to centering devices,
but jammed against the surrounding conduit wall.

This subclass is indented under the class definition. Apparatus comprising (a) a particular modification to a
pipe through the thickness or (b) means at the end of a conduit
for facilitating entry of the conduit into the well (e.g., casing shoes).

(1)Note. Claims to a plurality of well conduits may be classified
here, but conduits with attachments thereon other than shoes are
classified in subclass 243 or other subclasses according to the
features claimed.

(2)Note. Couplings for conduit sections are considered parts
of the conduit wall structure.

This subclass is indented under subclass 242.1. Conduit wall structure comprising means for introducing
an; e.g., cable or conduit, into the conduit wall through a bulged
or enlarged section of the conduit.

This subclass is indented under subclass 242.1. End structure comprising the particular shape, design, construction,
or configuration of the means at the terminus of a conduit for facilitating
entry of the conduit into the well (e.g., cementing shoes).

This subclass is indented under subclass 242.1. Conduit wall structure wherein the conduit wall is formed
of a hardened clay or powdered alumina, silica, lime, iron oxide
and magnesia material used in; e.g., water wells.

Hydraulic and Earth Engineering,
subclasses 132+ for tunnel structure and structure of shafts of
general utility; and subclasses 231+ for columnar foundation
structures (e.g., pier, pile) and methods and apparatus for installing
the same.

Earth Boring, Well Treating, and Oil Field Chemistry,
subclasses 200+ for processes involving no significant manipulative
steps or relationship with the well and consisting only of placing
a treating material in a well. Examples of broadly recited steps which
are not considered significantly manipulative are (a) generally
producing the well or (b) broad removal of spent material. Examples
of processes classifiable in Class 166 rather than Class 507 are:
using pressure; introducing one material after another; introducing
materials through separate conduits; introducing material at the
bottom of the well or below paraffin deposits; contacting well fluids
with an introduced material during pumping; producing or blowing
the well; a process in which materials are introduced into a well
to react with each other (including a process in which one material
reacts with the product of the reaction between another material
and a material found in the well); a process in which a material
is introduced in a special location, as between the casing and tubing;
or a process in which material is inserted into the pores of the
earth.

Colloid Systems and Wetting Agents; Subcombinations
Thereof; Processes of Making, Stabilizing, Breaking, or Inhibiting, appropriate subclasses for subject matter relating
to: colloid systems (such as sols*, emulsions, dispersions,
foams, aerosols, smokes, gels, or pastes) or wetting agents (such
as leveling, penetrating, or spreading); subcombination compositions
of colloid systems containing at least an agent specialized and designed
for or peculiar to use in making or stabilizing colloid systems; compositions
and subcombination compositions specialized and designed for or
peculiar to use in breaking (resolving) or inhibiting colloid systems;
processes of making the compositions or systems of the class; processes
of breaking (resolving) or inhibiting colloid systems; in each instance,
when generically claimed or when there is no hierarchically superior
provision in the USPC for the specifically claimed art.

This subclass is indented under subclass 244.1. A process in which an arrangement of more than two wells
in plan view is claimed with enough specificity to indicate a pattern
of wells (e.g., two lines of wells, one well surrounded by a ring
of other wells, etc.).

This subclass is indented under subclass 244.1. A process in which a biological organism of microscopic
or ultramicroscopic size (e.g., bacteria, etc.) is used.

(1)Note. A process involving using a bactericide or the like
to treat any microorganism which may be present but which is not
introduced as a part of the process is not included under this definition.
Such a process is classifiable on other features.

This subclass is indented under subclass 244.1. A process comprising (1) using nuclear energy or (2) using
radioactivity of a substance to effect some treating operation (e.g.,
heating the formation, etc.).

(1)Note. Nuclear energy in this subclass is energy created by
an induced nuclear reaction as described in the class definition
of Class 376, Induced Nuclear Reactions: Processes, Systems, and Elements.
Patents which claim well processes which recite a nuclear reactor
or details of the nuclear explosive are provided for in Class 376,
subclasses 273+.

This subclass is indented under subclass 244.1. A process in which rapidly pulsating forces of a mechanical
nature are applied to the earth, material in the pores of the earth
or material being injected into the pores of the earth.

(1)Note. The rapid pulsations must be in the sonic or ultrasonic
range, i.e., at least 15 cycles per second. Some disclosures do
not recite the rapidity of the vibrations. If, however, it is concluded
that the intent of the disclosure is to cover sonic or ultrasonic
vibrations, the patent should be classified under this definition.

(2)Note. A single explosion, implosion or blow may be followed
by rapid pulsations but such subject matter is not included under
this definition unless explosions or blows are repeated at sonic or
ultrasonic frequencies. See subclass 299 for a process including
an explosion, or implosion by breaking a container.

(3)Note. Vibrations applied to the earth merely for measuring,
testing, indicating, etc., are not included. A process with such
steps would be classifiable in subclasses 250.1+.

(4)Note. A process involving incidental vibration of the earth
or material in the earth, such as may take place when cementitious
material or gravel in a well is vibrated are not included. The
stated purpose of the process must be to impart vibrations or pulsations
to the earth or material in or being placed in the pores of the
earth.

This subclass is indented under subclass 244.1. Process including a step of: providing evidence of a condition;
e.g., leak, oil-gas interface; performing an analysis; e.g., downhole
pressure; counting; or determining the position of an object or
formation.

(1)Note. A process including a mere step(s) of indicating, detecting,
signaling, recording or measuring wherein the result is not related
to any other step in the claim is not classifiable here.

(2)Note. A process involving merely taking a sample of earth
fluid is not included under this definition. See subclass 264 for
such a process.

(3)Note. A process in which an inherent measuring step or the
like would take place, such as a process involving the use of a
fluid at a certain temperature, is not classified under this definition
unless a separate step of making the measurement, or the like, is
recited in a claim. Further, many well processes inherently give
a signal or indication when some well function is performed, such
as a pressure rise taking place when a plug closes an opening in
a cementing operation. Such processes, also, are not classified
under this definition unless some added indicating step is claimed.

Measuring and Testing,
subclasses 152.02+ for miscellaneous tests and measurements relating
to wells. Class 73 takes a process relating to measuring or testing
including steps relating to well features for perfecting the measuring
or testing process while Class 166 takes a more comprehensive process
relating to well conditions or structure which includes a measuring
or testing step.

Boring or Penetrating the Earth,
subclass 4.51for a gun or explosive charge perforating means
or step which inherently results in penetration of the earth in
combination with a position orienting or indicating means or step,
contributing to the effect of the perforating or penetrating means or
step, subclasses 40+ for processes or apparatus for earth
boring including signaling, indicating, testing or measuring and
especially subclass 45 for tool direction or inclination measuring
or indicating within the bore hole.

Communications: Directive Radio Wave Systems and
Devices (e.g., Radar, Radio Navigation),
subclass 22for transmission through media other than air or
free space, and subclass 459 for radar systems in wells.

Chemistry: Analytical and Immunological Testing,
subclasses 25+ for geochemical, geological, or geothermal exploration.
A nominal step in a claim, reciting drilling a well or recovering
fluid from the earth does not affect classification of a patent
in Class 436.

Data Processing: Measuring,Calibrating, or Testing,
subclasses 6 through 13for the application of well logging which requires
a mathematical calculation and only nominal recitation to the structure
of well logging.

This subclass is indented under subclass 250.01. Measuring or indicating including the step(s) of determining
the orientation, width, length, or pressure of the result of placing
a liquid or particulate material to erode a formation to increase
permeability.

This subclass is indented under subclass 250.01. Indicating including the step(s) of using or installing
a device to retain (a) a metal member to monitor the effect of corrosion
or (b) a detector within a well.

This subclass is indented under subclass 250.01. Measuring including the step(s) of determining the quality
or ingredients of (a) pipe to formation or pipe to pipe sealing
or adhering strength or (b) pipe stopper strength.

This subclass is indented under subclass 250.01. Testing including the step(s) of using an apparatus with
a single or plurality of inflatable sealing devices that reduce
or stop flow to monitor well parameters or change a well condition.

This subclass is indented under subclass 250.01. Indicating in which liquid or gas in the pores of the formation,
before the start of the process, is caused to be pushed towards
a well by another liquid or gas for flowing to the surface of the
earth.

This subclass is indented under subclass 252.1. Production of earth fluid by driving fluid including the
step(s) of determining the amount of (a) a compound that results
when, in an acid, the hydrogen is replaced by a metallic element or
compound or (b) a compound containing hydrogen in a fluid.

This subclass is indented under subclass 252.1. Production of earth fluid by driving fluid including step(s)
of monitoring a leading fluid in a process of pushing hydrocarbons
into a well using liquid or gas.

This subclass is indented under subclass 252.1. Production of earth fluid by driving fluid including step(s)
of determining a measure of the ease with which a fluid can flow
through a formation or a property of a fluid that causes the fluid
to tend to hold together as during flow.

This subclass is indented under subclass 252.1. Production of earth fluid by driving fluid including step(s)
of using an easily detectable composition (e.g., dye, inert gas,
halocarbons, cobalt-57, carbon dioxide).

This subclass is indented under subclass 250.01. A process including a step of determining or indicating
the position, diffusion or existence of plugging or consolidating
material.

(1)Note. For classification in this subclass a process must
have a step which relates directly to the subject matter rather
than to some step from which the position, presence or absence of
cement, etc., may be deduced. For example, a step of logging a well
may indicate the location to receive cement after a cementing operation,
or the process may include the step of indicating the pressure of
cement being pumped from which it may be deduced that cement is
present. Such steps are too indirect to be included. An example
of a process under this subclass is one in which the well is cemented
by a cement containing a radioactive material whose presence is
sensed to thereby determine the position of the cement.

This subclass is indented under subclass 250.01. A process in which some identifiable property of a portion
of a formation is ascertained.

(1)Note. The position determining steps must be explicitly recited
in a claim for classification in this subclass and not left to inference.
The position of a portion of the earth is almost always determined
at some stage in processes involving wells.

(2)Note. Included in this subclass are a natural property which
exists before any alteration by man and locating a radioactive marker
inserted in a formation.

This subclass is indented under subclass 254.1. Determining position of earth zone which includes the step(s)
of using a wireline operated device to traverse the formation.

(1)Note. The logging step must be explicitly recited in a claim
for classification in this subclass and not left to inference. The
position of a portion of the earth is almost always determined at
some stage in processes involving wells.

This subclass is indented under subclass 250.01. A process in which the location of a well completion device
in the well is ascertained.

(1)Note. The object must be something other than an instrument
used in a process for ascertaining the position of something.

(2)Note. A fluid or a formless substance is not considered an
object under this definition. A casing or tubing, however, is considered
an object.

(3)Note. For classification in this subclass some special step
for directly determining the position of an object must be recited
in a claim since the position of objects is generally known in well
processes or can be deduced from other information if so desired.

Boring or Penetrating the Earth,
subclass 4.51for subject matter relating to well perforating
by a bullet or shaped charge of an explosive combined with position
orienting or indicating and subclass 45 for boring tool position,
direction, or inclination measuring or indicating within the bore.

This subclass is indented under subclass 255.1. Determining position of an object including a step of setting
or arranging a device in a determinate position with respect to
other well structure or the formation.

This subclass is indented under subclass 256. A process in which material found in the earth is produced
from the top of a well due to in situ combustion taking place in
the pores of the earth, while at the same time material is being injected
into the pores of the earth from the same well.

This subclass is indented under subclass 256. A process in which plural, naturally distinct, vertically
related zones of earth are involved.

(1)Note. The distinct zones are usually identified by the fluid
they contain, such as oil or water. But where it appears that different
fluids are in a single zone having the same physical characteristics throughout,
the zone is considered to be a single entity.

(2)Note. It is common to produce a fluid from a formation located
between two or more other formations. Patents are classified in
this subclass only when the existence of plural distinct zones or
formation is a significant factor in the claimed process. A reference
in a claim to the top or bottom of a zone is not enough for classification
under this definition.

This subclass is indented under subclass 256. A process in which the earth is cracked to produce a fissure
or fissures therein, or in which fluid introduced into the pores
of the earth chemically reacts with the earth or deposits in the
earth to enlarge the pores of the earth.

(1)Note. See (1) Note in subclass 307 for a discussion of the
meaning of "deposits in the earth".

(2)Note. The fracture or pore enlargement must be effected by
some cause other than the heat of the in situ combustion itself.
A process in which the heat of the in situ combustion is said to
cause fracturing or increase of permeability is classified on other
features.

This subclass is indented under subclass 256. A process in which (1) a burnable substance is placed into
the pores of the earth and burned therein or (2) a catalyst for
affecting the burning operation is placed into the pores of the earth.

(1)Note. For classification as an original in this subclass
the burnable substance should be recited in a claim with some specificity
since it is very common to insert fuel into the pores of the earth
for in situ combustion. A mere recitation of a combustible mixture
of gaseous fuel and air or oxygen is not enough. However, a recitation
of a specific ratio of fuel to oxygen or air is sufficient. Also
a statement in a claim of the injection of fuel in a significant
sequence such as after an air injection is also sufficient.

(2)Note. "Burned" in the definition means a
vigorous union of a substance with oxygen.

(3)Note. A process in which a material is placed into the pores
of the earth for some other purpose and is not said to be burned
though it may actually be incidentally burned is not included under this
definition. Such a process would be classifiable in subclass 261.

This subclass is indented under subclass 256. A process in which a material is placed into the pores of
the earth, said material being other than oxygen, per se, or air.

(1)Note. A broad recitation of a combustion supporting gas or
a mixture of oxygen and an inert gas or of air enriched with oxygen
is not included. However, a recitation of a separate injection of
inert gas or a recitation of a specific ratio of oxygen in air or
inert gas is included, except a recitation such as 20% or
more oxygen in inert gas which is tantamount to a recitation of
air or air enriched with oxygen.

This subclass is indented under subclass 244.1. A process including a step in which a well is (1) used
for a period of time only to place material into the pores of the
earth and then for a period of time used only to produce fluid from
the earth or (2) used for a period of time to produce fluid from
the earth and then used (a) for a period of time only to place material into
the pores of the earth or (b) for a period of time is shut in to
stop flow of fluid from the earth.

This subclass is indented under subclass 244.1. A process comprising taking a limited amount of the fluid
in a well or the adjacent earth for testing or measuring purposes.

(1)Note. No special steps for limiting the flow need be set
forth for classification in this subclass. The mere statement is
a claim that a sample is taken is sufficient. Merely setting a
sampler in position, however, without the step of taking the sample
is not sufficient for classification in this subclass. Such processes
would be classifiable in subclass 315.

Measuring and Testing,
subclasses 152.02+ for a process or apparatus for taking a sample
from a well combined with making a determination of a physical characteristic
of a well, a borehole casing, or a drill rigging wherein the test
is not purely electrical or purely magnetic, in particular subclasses
152.07, 152.09, and 152.11 for core sample analysis for making a formation
logging wherein the test is not purely electrical or purely magnetic,
and subclasses 152.23+ for fluid flow measuring or fluid
analysis combined with sampling well fluid wherein the test is not
purely electrical or purely magnetic, and subclasses 863+ for
a process or an apparatus for sampling a fluid not in a well or
for a soil gas sampling process and apparatus.

Chemical Apparatus and Process Disinfecting, Deodorizing,
Preserving, or Sterilizing,
subclasses 50+ for apparatus for gas sampling involving use of
sorbents or chemical treatments which may include a shaft sunk in
the ground to collect gas for analysis.

This subclass is indented under subclass 244.1. A process comprising separating a stream of material which
has entered the well into two or more portions and as a result of
such separation delivering the material coming out of the top or head
of the well to two or more separate repositories or transmission
lines.

(1)Note. One of the repositories may be the same well from which
the material flows.

Chemical Apparatus and Process Disinfecting, Deodorizing,
Preserving, or Sterilizing, appropriate subclasses for sampling apparatus involving
the use of sorbents or chemical treatment. A well may be broadly
recited as a source.

This subclass is indented under subclass 265. A process including using a plurality of wells, at least
one of which receives a fluid for insertion into the pores of the
earth and another of which conveys a fluid from the pores of the earth
to the surface of the earth.

(1)Note. The line between this subclass and the various classes
relating to separation of fluids is that the positive recitation
in a claim of the step of placing a fluid in a well causes classification
in this subclass.

(2)Note. See subclass 265 for search notes on classes concerned
with fluid separations.

This subclass is indented under subclass 265. A process comprising separating the material coming out
of the well into two or more portions by steps taking place outside
of the well.

(1)Note. The line between this subclass and the classes concerned
with separation or treatment of fluids is that a process comprising
some significant steps of flowing or treating taking place in a
well combined with steps of separating the fluid after it leaves
the well is classified in Class 166, but a process including the mere
step of withdrawing fluid from a well is classified according to
the remaining subject matter of the process.

(2)Note. A method of pumping a well (classifiable, per se, in
Class 417, Pumps) combined with a method of separating fluid after
it leaves the well is classifiable in this subclass.

(3)Note. See subclass 265 for search notes on classes concerned
with fluid separation.

This subclass is indented under subclass 244.1. A process comprising a step of using a plurality of wells,
at least one of which receives a fluid for insertion into the pores
of the earth, usually to push hydrocarbons, and another of which conducts
the pushed hydrocarbons and fluid from the pores of the earth to
the surface of the earth.

(1)Note. Patents are classified as originals under this definition
even if the output well is not claimed if the sole disclosure is
for a process involving input and output wells, and a fluid claimed
as inserted into the formation is disclosed as a drive fluid. A "drive
fluid" is one which is continued to be inserted into the
formation until breakthrough or near breakthrough at an output well
occurs (e.g., the "water" in a waterflood process, etc.).
A patent describing a waterflood secondary recovery process or
the like which is not specifically disclosed as applicable to a
single combined input and output well is considered as drawn to
a sole disclosure of input and output wells even if the output well
is not mentioned.

Mining or In Situ Disintegration of Hard Material,
subclass 4for subject matter relating to input and output wells
utilized for in situ conversion of solid material other than hydrocarbon to
fluid for recovery.

Earth Boring, Well Treating, and Oil Field Chemistry,
subclasses 200+ for compositions for treating a well and processes
for using the compositions involving no significant manipulative step
or relationship with the well. A process including placing a composition
into the pores of the earth is considered to involve a significant manipulative
step or relationship.

This subclass is indented under subclass 268. A process in which fluid material is introduced into the
pores of the earth from locations in an input well which are spaced
from each other along the longitudinal axis of the well, i.e., vertically
spaced in the ordinary well having a vertical axis.

(1)Note. A location which is packed off from another location
is considered longitudinally spaced. A single group of holes in
a well conduit is not considered to provide longitudinally spaced
locations, but longitudinally spaced groups of holes do provide
spaced locations. Fluid introduced from an uncased portion of a
well is considered to be introduced from a single location.

(2)Note. A claim which calls for separate introduction of fluids
at locations longitudinally arranged in the well is considered to
meet the definition since such claim inherently requires the use
of a packer or equivalent means to effect the separate introduction.

This subclass is indented under subclass 268. A process in distinct, separate wells in which the fluid
temporarily alters the ease of flow through the formation by filling
in the pores for a specific time, usually immediately prior to a hydrocarbon
driving fluid.

This subclass is indented under subclass 268. A process in distinct, separate wells in which the fluid
is a wetting agent that causes the lowering of interfacial tension
between two fluids; e.g., water and oil.

(1)Note. The term "surface active agent" also
describes this type of material.

This subclass is indented under subclass 268. A process in which the earth is cracked to produce a fissure
or fissures therein or in which fluid introduced into the pores
of the earth chemically reacts with the earth or deposits in the
earth to enlarge the pores.

(1)Note. See (1) Note in subclass 307 for a discussion of the
meaning of "deposits in the earth".

Boring or Penetrating the Earth,
subclass 12for processes or apparatus for forming a bore by
combustion of the earth formation material and subclass 17 for processes
or apparatus including heating within the bore or heating the drilling
fluid used in boring.

Mining or In Situ Disintegration of Hard Material,
subclass 4for subject matter relating to input and output wells
utilized for in situ conversion of solid material, other than hydrocarbons,
to fluid for recovery and generally including the use of heat.

This subclass is indented under subclass 272.3. Steam drive including a substance having (a) univalent aliphatic,
aromatic-aliphatic, or alicyclic hydrocarbon radical or (b) the
element carbon in a chemical string.

This subclass is indented under subclass 268. A process in which a fluid mixture or solution comprising
water and a material other than an inorganic gas, is introduced
into the pores of the earth.

(1)Note. The "material" must be other than a
material which is already present in the source water. Thus a natural
brine would not comprise an added "material" but
a naturally occurring water to which salt has been added would have
an added "material".

(2)Note. See (1) Note in subclass 268 for the classification
of a patent claiming placing a fluid into the formation but not claiming
an output well.

and 274, for a process involving input and output
wells in which two or more separate fluids are introduced into the formation.
Patents in subclasses 273 and 274 which disclose significant species
relating to introducing a single fluid mixture or solution comprising water
and a material other than inorganic gas should be cross-referenced to
subclass 275.

This subclass is indented under subclass 244.1. A process comprising establishing a mass of material having
small irregular interstices in the well at the location where earth
fluid enters the well so as to act as a filter for such fluid.

(1)Note. The material may be made porous before or after it
is placed in the well. It must continue to be an adhered mass after
being made porous.

(2)Note. The mass of material must be coherent or made of adhered
particles. A bed of separate unadhered particles such as a gravel
bed is not included. See subclass 278 for a process of making an unadhered
bed of particles.

and the subclasses there noted for a process of
cementing, plugging or consolidating which may include establishing
a porous mass of adhered particles in the formation, especially subclass
295 for a process in which the cementing or consolidating material
is or has an ingredient which is a resin.

This subclass is indented under subclass 244.1. A process comprising repairing an object in the well (e.g.,
connecting broken ends, stopping leaks through the casting wall,
replacing a casing section, etc.).

This subclass is indented under subclass 244.1. A process comprising making a bed of gravel or other filter
material in situ in the well for straining fluids flowing into the
well.

(1)Note. This definition does not include a process involving
merely forming a bed of filter material outside of the well and lowering
it into the well. See subclass 315 for a process of making a well.

(2)Note. This definition includes washing away earth around
a well conduit to form a bed of gravel or the like. Processes involving
merely cleaning a well, however, would be classified in subclasses 311+ and
processes involving attacking a formation would be classified in
subclass 307 or the subclasses there noted.

(3)Note. Making a bed of gravel or filter material in the formation
is not included. Note subclass 280 for propping material in a fracture
and subclasses 285+ and the subclasses there noted for
permeable material deposited in the formation.

This subclass is indented under subclass 244.1. A process comprising placing material into the pores of
the earth so that fluid which was in the pores of the earth before
the start of the process will be treated to acquire some beneficial
property (e.g., corrosion inhibiting, etc.) as it flows past the
material to enter the well.

(1)Note. Merely flushing out a material (e.g., an acid, etc.)
which has been placed in the pores of a formation by flow of fluid
from the pores of the earth without any desired beneficial property being
given to the earth fluid does not come within this definition. Such
processes are classified in subclass 305 and the subclasses there
noted.

This subclass is indented under subclass 305.1. A process comprising some claimed specific feature relating
to placing discrete particles in a fracture in a formation to maintain
the walls of the fracture spaced apart by resisting forces tending
to close the fracture.

(1)Note. For classification as an original under this definition
the specific feature must be more than merely identifying the propping
material as sand, or the equivalent, or merely the use of a specific
fluid containing the propping material or merely the introduction
of the propping material in one of a series of fracturing fluids.

(2)Note. Placing in a fracture a slurry of cement which sets
and remains in place as an adhered mass and which cement may contain
hard particles dispersed therein is not considered to come within this
definition. For a process involving cementing see subclasses 281,
283 and 285. This definition does include, however, a process in
which discrete propping particles are adhered together after being
placed and a process in which propping particles are incorporated
in a carrier fluid, which may be cement (such as a gel), and the
carrier fluid is changed in nature, or removed, or is of such a nature
that the discrete particles themselves resist closing of the fracture
rather than a mass of cement in which the particles are embedded
resisting closing of the fracture.

(3)Note. A process in which discrete particles are placed in
a fracture so that the particles are crowded together or compacted
to plug the fracture to impede the flow of fluid is not considered
to come within this definition. See the subclasses relating to cementing
or plugging, especially subclass 292 for such a process.

(4)Note. Discrete particles in a fracture which are described
merely as forming a filter will be assured also to act as props and
be classifiable under this definition.

(5)Note. Included in this subclass are the foreign patent documents
from ECLA (E21B 43/267).

This subclass is indented under subclass 244.1. A process in which a part of the process relates to (1)
cementing, plugging or consolidating and a separate part of the
process relates to (2) fracturing or attacking the formation.

(1)Note. See the definition of subclasses 307 and 308 for the
meaning of attacking the formation and fracturing the formation,
respectively.

(2)Note. It is not considered two separate parts of a process
if a single stream or volume of one fluid composition performs both
functions (1) and (2). See subclasses 282 and 283 for such processes.

(3)Note. It is not considered two separate parts of a process
performing functions (1) and (2) if the process is for forming a fracture
by cementing, plugging or consolidating material and as a separate
step forming another fracture by such material. Such process would
be classifiable in subclass 283.

This subclass is indented under subclass 244.1. A process in which a fluid is introduced into the pores
of the earth to chemically react with the earth or deposits in the
earth to enlarge the pores of the earth and there is a specifically claimed
feature of the process for limiting travel of the fluid in the pores
of the formation.

(1)Note. See (1) Note of subclass 307 for the meaning of "deposits
in the earth".

(2)Note. The feature to limit travel of the fluid may relate
to an addition in the fluid or to another material placed in the pores
of the formation or in the well in contact with the formation acting
to limit or block flow of the attacking fluid in all directions
or to deflect the flow to a desired direction. A mechanical means for
directing flow such as a packer in the well bore is not included.
The blocking or flow directing material is sometimes called a blanketing
material.

for processes relating to separate steps for (1)
cementing, plugging or consolidating and (2) attacking the formation
in which the cementing, plugging or consolidating material may limit loss
of the attacking fluid.

This subclass is indented under subclass 244.1. A process in which the earth is cracked by a fluid in order
to create a fissure or fissures therein and in which (1) there is
a specifically claimed feature for limiting travel of the fluid in
the pores of the formation or (2) the fluid is a cementing, plugging
or consolidating material.

(1)Note. See (2) Note of subclass 282 for the meaning of the
feature to limit travel of the fluid.

for processes relating to separate steps of (1)
cementing, plugging or consolidating and (2) fracturing, in which
the cementing, plugging or consolidating material may limit fluid
loss of the fracturing fluid.

This subclass is indented under subclass 244.1. A process in which there is an opening in the side wall
of a pipe or well conduit and a pellet entrained in a fluid is caused
to be moved by said fluid to impede flow of said fluid through the
opening, a single pellet being used to impede flow through an opening.

(1)Note. Plural pellets may be used to block plural openings
but only one pellet is used for each of the openings blocked by
the pellets. If a plurality of pellets or particles are used to
block an opening the operation is considered to be a cementing or
plugging process for subclasses 285+.

(2)Note. The pellet must be free to travel a substantial distance
due to fluid flow. A pellet confined in a cage adjacent an opening
which pellet is moved by fluid flow to block the opening is considered
a check valve. A process using such a pellet would be classified
on other features.

This subclass is indented under subclass 244.1. A process comprising (1) causing fluent material to flow
into position in prepositioned well conduit substantially to stop
flow of a fluid by forming a blocking means in situ, said material being
plastic or hardenable after being so placed, (2) placing small particles
in a prepositioned well conduit to cause them to form a mass of
particles in situ substantially to stop flow of a fluid, (3) placing
or forming solid or plastic material in the pores of or spaces in
a formation to block them and thereby impede flow of an earth fluid,
(4) treating a formation with an introduced material so as to prevent
it from shifting or breaking down, i.e., consolidating the formation,
or (5) treating a formation (e.g., by heating, etc.) to cause the formation
to coalesce into an impermeable or consolidated mass.

(1)Note. Patents with claims in which there is only a broad
mention by name only of a cementing, plugging or consolidating process
with no detail of the steps of the process or the material used,
are classified on the basis of the other steps recited. In the
case, however, of a drilling process in which drilling is interrupted
for cementing, classification may be in subclasses 285+ even
if the cementing step is only nominally or inferentially claimed.
See section III of the class definition. However, if any other
steps are set forth in a claim affording a basis for classification
in a subclass below subclasses 285+ then the patent is classified
in the appropriate subclass, the nominal cementing step being disregarded.

(2)Note. Processes which include forming a coating or lining
on the bore hole wall or plugging the pores of the formation by drilling
fluid while the earth in being cut or disintegrated to form the
bore, are not classified as cementing, plugging or consolidating
processes for this class. See section III of the class definition
of Class 166 for the line with Class 175, Boring or Penetrating
the Earth, and the search notes below.

(3)Note. Merely forming a plug or the like by lowering a quantity
of plastic material in a container and permitting it to harden in
the container is not included. See subclass 315 for such processes.

(4)Note. Under this definition material deposited in the openings
of a formation may block one fluid and not another, or may form
a permeable mass.

(5)Note. Material deposited in the formation to form a film
or thin coating on the formation material, or to form a foam, is not
considered to come within this definition. See subclasses 305+ and
the subclasses there noted for processes for so treating the formation.

(6)Note. Material deposited in a fracture to form discrete props
for the fracture is not considered to come within this definition.
See subclass 280 for processes involving a specific propping feature
and see (3) Note in said subclass for the distinction between propping
and cementing or plugging.

Static Structures (e.g., Buildings),
subclasses 741.11+ for a process of construction or assembling of
a building, e.g., cistern or well, made by workmen operating on
an exposed face of such a structure.

Adhesive Bonding and Miscellaneous Chemical Manufacture, appropriate subclasses for processes and apparatus for
laminating in general and see especially
subclasses 293+ and 423+ for inserting a core within a tube.

Boring or Penetrating the Earth,
subclasses 65+ for processes of boring with a fluid and especially
subclass 72 for such processes which include prevention of lost
circulation or caving while drilling. See section III of the class
definition of Class 166 for the line between Class 166 and Class
175.

Hydraulic and Earth Engineering,
subclass 57for processes of cementing fluid reservoirs in
the earth by means operated from the earth surface; subclasses 130+ for
processes of applying heat to or removing heat from an earth formation;
subclasses 233+ for casting a pile in situ from hardenable
fluent material; and subclasses 263+ for applying a chemical substance
to an earth formation to condition the same, especially subclasses
266+ for cementitious substances, except that patents disclosing or
claiming treatment of a well or treatment of the earth around a
well are classified in Class 166.

Synthetic Resins or Natural Rubbers, appropriate subclasses, particularly Class 523,
subclasses 130+ for a composition having utility in consolidating
a formation in a well or in cementing a well or to processes of preparing
said composition.

This subclass is indented under subclass 285. A process comprising placing cement by (1) using a container
of the cement in a well, (2) exploding the cement against the bore
hole wall, (3) vibrating the cement while in the bore hole, or (4)
striking the cement in the bore hole a blow or series of blows.

This subclass is indented under subclass 285. A process in which a mold or forming means is used to hold
the cement, the mold or forming means being removed from the well
bore after the cement has set and been shaped by the mold or form.

This subclass is indented under subclass 285. A process involving the use of a significant or substantial
amount of heat.

(1)Note. The use of heat in preparing a cementing, plugging
or consolidating material above ground is not included. See subclasses
292+ for such a process.

(2)Note. The presence of heat must be positively stated in a
claim for classification of a patent in this subclass. An inference that
heat is present, as because of a chemical reaction, is not sufficient
for classification in this subclass.

(3)Note. Merely permitting the natural heat present in the well
to act on cementing, plugging, or consolidating material is not included.
See subclass 295 for methods involving the use of resins set by
the natural heat of the well.

This subclass is indented under subclass 285. A process in which cementing, plugging or consolidating
material is caused to issue from a single string of well casing
at a plurality of levels.

(1)Note. A group of substantially evenly spaced perforations
in a casing out of which cementing, plugging or consolidating material
may issue is considered a single level rather than a plurality of
levels.

This subclass is indented under subclass 285. A process comprising placing the cementing, plugging or
consolidating composition by means of a well tubing, the lower end
of which is lifted from the level at which the composition is placed,
after placement.

This subclass is indented under subclass 285. A process comprising forcing the cement down a tubing or
casing in the well and separating the traveling body of cement from
an adjacent fluid by a piston means at an end of the cement body.

(1)Note. The piston means may itself comprise a fluid of limited
longitudinal extent which functions like a solid piston.

Boring or Penetrating the Earth,
subclasses 64and 65+, especially subclass 72, for drilling
while circulating fluid which may form a mud sheath or plug the
formation. See Lines With Other Classes and Within This Class in
the class definition of Class 166 for the line between Class 166
and Class 175.

This subclass is indented under subclass 292. A process in which the material which causes cementing,
plugging or consolidating comprises a mixture of an organic material
and an inorganic material which hydrates to become hard or plastic.

(1)Note. Clays, for the purpose of this definition, are not
considered to be materials which hydrate to become hard or plastic.

(2)Note. The material of the definition must be a slurry which
is considered to form an intermingled mixture of organic and inorganic
cementing, plugging or consolidating materials when in final position
in the well or formation. If the organic and inorganic materials
were considered to be separate or separate in the formation or well
so that only one of them performs the cementing, plugging or consolidating
function, then classification would be on some other basis, probably
in subclasses 292 or 294+.

This subclass is indented under subclass 244.1. A process comprising the steps of preventing the flow of
earth fluid into a well conduit through the openings of a preformed
strainer or preformed filter while it is being lowered through a
producing formation and then permitting flow of earth fluid through
said openings to produce the well.

This subclass is indented under subclass 244.1. A process comprising forming a hold, weakening a localized
portion, bending or separating portions of a pipe at any suitable
location which has not previously been prepared to make it easier
to operate on.

(1)Note. The earth wall of the well or a cake left on the formation
by circulating fluid while drilling a bore is not considered a pipe
wall, but a cementitious wall of a well conduit made by the process defined
in subclass 285 or made above ground is considered a pipe wall.

(2)Note. In processes relating to an above ground location some
significant well feature should be present for classification in
this subclass, but for processes taking place below ground a disclosure line
is followed except for those processes provided for in other classes.

(3)Note. The term "bending" in this definition
is limited to bending which causes a change in the direction of
the longitudinal axis of the pipe. Processes involving expanding
a pipe wall may be found in subclasses 277 and 315.

Boring or Penetrating the Earth,
subclasses 2+ for processes of firing a bullet or exploding a
shaped charge from an inaccessible bore for perforating a wall member
in the bore if the process inherently result in penetration of the
formation.

This subclass is indented under subclass 297. A process in which the wall portion of the pipe is perforated,
weakened or separated by (1) a mechanical cutting, punching or abrading means
or (2) a jet of fluid containing an abrasive.

(1)Note. A projectile propelled by an explosive jet of fluid
such as that produced by a shaped charge is not included. Processes
using such projectiles or jets are classifiable in subclass 297
or Class 175, Boring or Penetrating the Earth, subclasses 2+.

Cutting,
subclasses 13+ for cutting methods in general, especially subclass
54 for a method of cutting the wall of a hollow workpiece, and subclass
177 for apparatus for cutting by fluid blast and/or suction.

Boring or Penetrating the Earth,
subclasses 2+ for processes or apparatus for forming a bore hole
by below ground explosion, or perforating or cutting a casing or
other bore lining by firing a bullet or exploding a shaped charge
in an inaccessible bore.

This subclass is indented under subclass 244.1. A process comprising placing from above ground level, two
or more materials into the well which chemically react with each
other in the well or earth.

(1)Note. The reaction may be between one introduced material
and a product produced by the reaction of another introduced material
with a material found in the well.

(2)Note. The word "material" in the definition
is intended to mean an unformed or particulate material or a material
which has a form for purposes of the process but is not a device
such as a tool, pipe, closure disk, or the like, which has an independent
function in the well.

This subclass is indented under subclass 244.1. A process for (1) releasing an object in the well from a
condition which prevents it from being moved, (2) grappling for
an object in the well or (3) retrieving a small, loose object from inside
the well.

(1)Note. A process under part (1) of this definition must involve
more than merely disconnecting two parts, severing a part so as
to leave a stuck portion in the well and free the severed portion
or unsetting a device like a packer; a special procedure must be
used to free a member held fast in the well by a condition such
as corrosion or cave-in of the formation. A process under part (2)
of this definition relates to a process for using the grapple apparatus
found in Class 294, Handling: Hand and Hoist-Line Implements, especially
subclasses 86.1+; a process for merely affecting a pipe
joint or coupling is not included, such process when used in a well
being classifiable in subclass 315. A process under part (3) of
the definition relates to a process for using the fishing means found
in Class 294, especially subclasses 86.1+, or in Class
166, subclass 99.

for a process of cleaning which may be similar to
a process in subclass 301 but not for freeing a stuck object, grappling
or fishing in the well. For example, a process for bailing sand from
a well would be classifiable in subclasses 311+ whereas
a process for fishing, e.g., recovering a small discrete object
from the well rather than a particulate mass of material, would be
classifiable in subclass 301.

This subclass is indented under subclass 244.1. A process in which there is a heating, cooling, or insulating
step or a heated or cooled material is used.

(1)Note. A mere welding step is not included. See the search
notes below.

(2)Note. The cooling effect of gas flowing through a choke is
not subject matter for this subclass unless said effect forms a part
of the method being claimed. Processes involving wells flowing
through chokes may be classified in subclass 314.